Copyright: ©1994 Digital Equipment Corporation
Citation: ©1994 Digital Equipment Corporation


Contents

DECpc XL Series Field Service/Field Training - Version 1.0

The following Help Topics or groups of Help Topics are available:

About This Help System

Introduction

General System Features

System Utilities & Configuration

928/PCI Video Adapter

Expanding Your Computer

Computer Messages

Problem Solving and Troubleshooting

Device Mapping

FRU List (Part Numbers)

Technical Specifications

Related Material

For Help on Help, Press F1


General System Features

i486/PCI CPU Features

Pentium/PCI CPU Features

PCI Features

Standard Computer Features

Standard Slots and Ports

Storage Bay Features

Front Panel Controls and Indicators

Rear Panel Connectors and Voltage Select Switch


System Utilities & Configuration

Utilities and SCSI Drivers Diskettes

Using the System Utilities Diskette

About UPGRADE.EXE

Creating a Recovery Diskette

Upgrading Your Computer's BIOS

Running SETUP.EXE

Configuring Your Computer

Running the BIOS Setup Utility

BIOS Setup Utility Options

Running KP.EXE


About This Help System

This topic is designed to help you understand the way this Help file has been organized and the graphic and stylistic conventions which have been used in presenting the material.

Organization

There are several "layers" of contents pages in this Help file, each grouping a related set of Help topics.  The topics are also selectively cross-referenced, so that you can jump quickly between Help topics grouped in different sections of the file.  Simply click on the highlighted words, phrases, and topic titles to move from topic to topic.

Enhanced Illustrations

Where parts of an illustration (such as lettered callouts) appear boxed by dotted lines, you can click on the boxed area to see further information about the item being illustrated.  Note that if you have significantly reduced the size of the Help window, some illustrations may not be completely visible and/or the scrollable area of the window may become too small to display text.  If this happens, simply increase the size of the Help window until all the information you need becomes visible or can be scrolled into view.

The illustrations in this Help system have been designed for high-resolution display.  You should set your monitor to the highest possible screen resolution in order to view the illustrations most clearly.

Color

Information of special importance has been indicated in this Help file by the use of colored text: blue for NOTE, red for CAUTION, and dark red for WARNING.  (If your system is equipped with a monochrome display, these colors will appear as BOLD text.)  You may find some of this colored text difficult to read if you have made changes in your Windows screen colors.  This problem can be solved by returning the color settings to one of the pre-defined Windows color sets while you are using the Help file.

Entire contents of this Help file copyright © 1994 Digital Equipment Corporation.


Introduction

DECpc XL Series computers are high-performance personal computers equipped with the latest microprocessor and PCI local bus technology.  They can be used as stand-alone computers, as clients, or as servers in an network environment.  Developed using modular CPU technology and offering a host of high-performance options, the DECpc XL Series offers you the most advanced computers in their class.  Note that your monitor, keyboard, and mouse might look different from the one shown.

Your computer's modular CPU board technology allows you to use the latest Intel i486™- and Pentium™-based microprocessor available today, while enabling easy computer upgrades to CPU technologies of the future.  The Intel i486-based CPU module is also designed to support the Intel Pentium OverDrive™ CPU upgrade.  This flexible design architecture helps protect your initial computer investment as your computing needs grow in future years.

Computer Description
All DECpc XL Series computers are industry-standard Intel i486 or Pentium microprocessor-based PCs using a versatile micro-tower enclosure.  The computer features a modular CPU board design that allows easy computer upgrades to the latest available CPU technology.  Intel i486-based CPU modules use an Intel Pentium OverDrive Ready ZIF socket to allow CPU upgrades to future Intel Pentium microprocesor technologies.  Intel Pentium-based CPU modules offer full 64-bit processing with ZIF technologies upgradeability via future Intel OverDrive CPUs.


Pentium/PCI CPU Features

Your DECpc XL Series computer may contain an Intel Pentium CPU.  The Pentium CPU and related high-performance caching circuitry are located on a CPU module connected to the main logic board inside your computer.  Pentium/PCI CPU features include:

•	Pentium CPU operating at 60 or 66 MHz

•	Standard 256 KB of secondary cache memory

•	ZIF socket for CPU upgrades


i486/PCI CPU Features

Your DECpc XL Series computer may contain an Intel i486 CPU.  The i486 CPU and related high-performance caching circuitry are located on a CPU module connected to the main logic board inside your computer.  i486/PCI CPU features include:

•	i486 CPU operating at 33 or 66 MHz internally (33 MHz externally)

•	Standard 128 KB secondary cache memory, optionally expandable to 256 KB

•	ZIF socket for CPU upgrades


PCI Features

Your computer's PCI architecture delivers maximum computer performance by providing a wider data path, greater speed, and improved expandability.  Simply put, PCI removes various types of peripheral controllers from the slower ISA and EISA buses and connects them directly to a wider, faster data path.  This results in faster data transfers for devices such as SCSI controllers and high-end video adapters.  This is extremely important while running graphic-intensive software.  Features include:

•	Highest performing bus on the market today

•	Offers the best expandability for high-performance peripheral devices

•	Supports multiple bus masters

•	32-bit data transfer at 120 MB per second (maximum)

•	PCI-to-ISA bridge circuitry allows continued use of existing ISA expansion boards on the market that do not require the high data transfer rate of PCI


Standard Computer Features

IDE	Dual IDE controller - supports 2 drives and 32-bit accesses under Windows

Floppy	Dual floppy controller - supports 2 drives:
720 KB, 1.44 MB, and 2.88 MB 3½-inch drive, and
360 KB, 1.2 MB 5¼-inch drive

SCSI	Onboard 53C810 NCR PCI SCSI controller

Supports up to seven SCSI devices (i.e., hard disk drives, CD-ROMs, etc.) on either the internal SCSI cable or on an external SCSI cable connected to a SCSI expansion box


Storage Bay Features

Front access	1 - 3½-inch (floppy) 1-inch high
3 - 5¼-inch half-height bays (optional storage devices)

Internal	1 - 3½-inch half-height bay (hidden for hard disk use)

See also:	 Front Panel Controls and Indicators


Standard Slots and Ports

Expansion slots	4 ISA slots and 2 PCI 32-bit local bus slots or
3 ISA and 3 PCI 32-bit local bus slots

Serial COMM ports	2 serial ports - 16550 compatible

Printer port	1 parallel (bi-directional)

Mouse	PS/2 compatible

Keyboard	PS/2 compatible

See also:	Rear Panel Connectors and Voltage Select Switch


Front Panel Controls and Indicators

To determine the purpose and function of a particular control or indicator on the front panel, click on the relevant portion of the illustration below.


drive bays

These are the upper 5¼-inch drive bays.


hard drive

This is the hidden (internal) 3½-inch drive bay.


3½-inch diskette drive

This is the factory-installed 3½-inch diskette drive.


diskette eject button

Pressing this button releases a 3½-inch diskette inserted in the diskette drive.


power on/off button

This button turns ac power on and off.


reset button

This button resets the computer and causes the POST to run.


power light

The power light is lit when the computer is on.


hard disk drive light

The hard disk drive light is lit when a hard disk drive is in use (IDE and SCSI).


turbo light

The turbo light is lit when the computer runs at the rated microprocessorspeed.  Indicator is off when the computer runs in non-turbo mode (8 MHz).


Rear Panel Connectors and Voltage Select Switch

To determine the purpose and function of a particular connector or switch on the rear panel, click on the relevant portion of the illustration below.


ac output connector

Allows you to connect a monitor to ac power.


ac line connector

Allows you to connect the computer to an ac power source.


mouse connector

Allows you to connect a PS/2 compatible mouse.


keyboard connector

Allows you to connect a 101-key or 102-key keyboard.


serial port connectors

These ports allow you to connect serial devices, such as an external modem.


SCSI port connector

Provides the interface between the computer and an external SCSI device.


analog video connector

Provides the interface between a video adapter and a supported monitor.  (This connector is found on PCI video cards such as Digital's 928/PCI Video Adapter card.)


parallel port connector

This port allows you to connect an industrystandard parallel printer.


ISA expansion slots

These slots allow you to install up to three ISA expansion boards.


PCI expansion slots

These slots allow you to install up to two PCI local bus expansion boards..


ISA/PCI shared expansion slot

This slot allows you to install either a fourth ISA expansion board or a third PCI local bus expansion board.


chassis lock

Locks the outside panels to prevent unauthorized access.


voltage select switch

Allows you to switch from 115 V ac input power to 230 V ac input power.


Utilities and SCSI Drivers Diskettes

Your computer comes with the following Utilities and SCSI Drivers diskettes:

•	System Utilities  — this MS-DOS bootable diskette contains the following files:

−	SETUP.EXE — allows you to run an MS-DOS executable version of the BIOS Setup utility

−	KP.EXE — allows you to set a keyboard and mouse password

−	UPGRADE.EXE — allows you to upgrade or repair your computer's BIOS via Flash ROM

•	MS-DOS/Windows, Windows NT, Netware, and OS/2 NCR SCSI Drivers — For additional information on the directory structure for locating the driver file you need, see the README.TXT file on the supplied SCSI driver diskette.  For installation and other instructions, refer to the supplied SCSI Device Management System User's Guide.

•	NCR SCO UNIX SCSI Drivers — For additional information on the directory structure for locating the driver file you need, see the README.TXT file on the supplied SCSI driver diskette.  For installation and other instructions, refer to the supplied SCSI Device Management System User's Guide.

Before Using the Supplied Diskettes

If you are unfamiliar with utility programs, SCSI drivers, and their uses, carefully read and understand the following information before attempting to use any diskette.

Also, make sure your computer operates as expected following the instructions in Chapter 1 of your User's Guide.

See also:	Configuring Your Computer
 "SCSI Help"


Using the System Utilities Diskette

This diskette allows you to:

•	Run an MS-DOS executable version of the computer's BIOS Setup utility (SETUP.EXE)

•	Set a keyboard and mouse password (KP.EXE)

•	Upgrade or repair the computer's BIOS (UPGRADE.EXE)

NOTE	If this is the first time using the System Utilities diskette, it is recommended that you follow the procedures in the order given.

1.	Make a backup copy of System Utilities diskette and then store original in a safe place.

2.	Turn on or reboot your computer.

3.	Insert backup copy of System Utilities diskette into drive A.

4.	Run UPGRADE.EXE.

5.	Run SETUP.EXE.

6.	Run KP.EXE.

7.	Remove System Utilities diskette and then reboot computer so changes immediately take effect.


UPGRADE.EXE
About UPGRADE.EXE

All computers have BIOS software in a read-only, non-volatile memory (ROM) chip.  This BIOS initializes hardware and boots the operating system when the computer is turned on.  The BIOS also provides access to other services such as keyboard and disk drives.

Your computer comes equipped with flash memory.  This means that you can repair your computer's BIOS simply by running the UPGRADE.EXE utility contained on the supplied System Utilities diskette.  You can also upgrade your computer's BIOS to future releases by running UPGRADE.EXE along with any flash BIOS update diskette if necessary.

Before Using UPGRADE.EXE


Before Using UPGRADE.EXE

If you are not familiar with utility programs and their uses, carefully read and understand the following information before attempting to use UPGRADE.EXE.

Make sure your computer operates as expected using the instructions in Chapter 1 of your User's Guide.

Have the following items available before you begin:

•	Blank formatted diskette

•	System Utilities diskette (supplied with your computer)

•	Recovery diskette

NOTE	Before attempting to upgrade the flash BIOS, ensure that J35 is set correctly.  To perform a flash BIOS upgrade, J35 must be set to enable.  After the upgrade, make sure J35 is set back to disable as a security measure (if desired).

See also:	Creating a Recovery Diskette
Technical Specifications


Creating a Recovery Diskette

1.	Insert backup copy of System Utilities diskette into drive A.

2.	Turn on your computer.

3.	At MS-DOS prompt, type a:upgrade, and then press [Enter].

This invokes UPGRADE.EXE.  Also, the following menu items appear on the screen:

Make Recovery Diskette from Flash
Make Recovery Diskette from Image File
Upgrade Flash from Image File
Save Flash to Image File
Compare Flash to Image File
BIOS Information
Exit

For additional on-line help,  press [F1].

4.	Select Make Recovery Diskette from Flash menu option.

The message, "Please select the diskette drive that you will use to create a Flash Recovery Diskette, or select "Cancel" to abort," appears on screen.

5.	Press [Tab] or up and down arrow keys to highlight diskette drive you want to use, then press [Enter].   Drive A is the default diskette drive.

The message, "Insert a formatted diskette into drive A.  The contents of this diskette will be lost!  and replaced with system recovery software and the BIOS image you specified.  Select "Continue" to start writing the recovery diskette, or "Cancel" to abort," appears on screen.

6.	Insert a blank (formatted) diskette in drive A, and select Continue to proceed with creating a recovery diskette.  A message window notifies you when it completes.  Press any key to continue.

7.	Remove recovery diskette and store it in a safe place.


Upgrading Your Computer's BIOS

1.	Insert System Utilities diskette in drive A.

2.	Select Upgrade Flash from Image File menu option.

You are then prompted to select a BIOS image file to program into flash memory.

NOTE	If your BIOS resides on a diskette, you need to use that diskette to upgrade your BIOS.

3.	Press [Enter] to list a directory of .BIN (BIOS image) files.  Select the image file you want to use.

The message, "Your BIOS will now be replaced by the new BIOS image you selected.  Select "Program" to start, or "Cancel" to abort.  Keep in mind that programming a new BIOS into Flash memory requires a fair amount of power.  If you are running on battery power you should have a full charge!" appears on screen.

4.	Press [Enter] to continue programming new BIOS into flash memory.

The message, "DO NOT TURN OFF THE POWER," appears on screen.

The flash memory is erased, and replaced by new BIOS.  Depending on size of flash memory, programming takes 20-40 seconds.  When programming completes, a message briefly appears on screen, then computer attempts to reboot.

5.	Remove System Utilities diskette and allow computer to reboot without error.

If an error occurs, a siren sounds while your computer attemps to boot signaling that your flash memory is corrupted.  If this occurs, insert recovery diskette into drive A or B so original BIOS can be copied back into flash memory.

If computer does not reboot and siren does not sound, turn off your computer.  Set main logic board jumper J34 to recovery mode.  This forces a BIOS recovery process.

⇒	See Technical Specifications

6.	Insert System Utilities diskette into drive A, invoke UPGRADE.EXE, and select Compare Flash to Image File menu option.

The message, "Select BIOS Image File Name to compare against flash memory," appears on screen.

7.	Press [Enter] to display a list of .BIN (BIOS image) files.  Select .BIN file you want to compare with flash memory.

A message window shows whether flash memory contains same BIOS as disk file.

Press any key to continue.

8.	If applicable, select Save Flash to Image File menu option.  This option reads BIOS out of flash memory and stores it on a disk file.  A valid image file can be used with other upgrade commands that need an image file.

The default name for image file is DEFAULT.BIN.  You can type in a different file name if you do not want to use the default name.

9.	Exit UPGRADE.EXE and remove System Utilities diskette.


SETUP.EXE
Running SETUP.EXE

SETUP.EXE allows you to select and permanently store information about the computer's installed hardware and software in the battery-backed memory of the CMOS RAM.  This information takes effect each time the computer boots and can be changed each time you run Setup.

To access SETUP.EXE:

1.	Turn on your computer.

2.	Allow POST to complete.

•	If an error message appears on screen, see Computer Messages,

3.	Insert backup copy of System Utilities diskette into drive A.

4.	Type a:setup then press [Enter].

Page 1 of Setup appears.

5.	Press right arrow key to move cursor to ROM Based Setup option.  Change setting to Enable/Disable.

•	See also:	Configuring Your Computer

6.	Exit SETUP.EXE (saving the changes).

7.	Remove backup copy of System Utilities diskette and reboot your computer.


KP.EXE

KP.EXE is an MS-DOS executable file that allows you to set a password for the keyboard and mouse without turning off your computer.  When you set this password, the keyboard and mouse can not process any input other than the current keyboard and mouse password.  Setting this password secures your computer against unauthorized access while your computer remains turned on.

If you set a keyboard and mouse password, each time you turn off your computer, the password is deleted.  When you turn on the computer again, you must set a new keyboard and mouse password.  When you have a power-on password set, the     power-on password becomes the keyboard and mouse password.

Keyboard and mouse passwords can have as many as seven upper or lower case keyboard characters and is recorded exactly as you enter them.  For example, if you use the 6 from the typewriter key section of the keyboard, you cannot substitute the 6 from the numeric keypad.

NOTE	When you create a keyboard and mouse password, the characters do not appear on the screen as you type them.  Each time you enter or change a keyboard and mouse password, the characters also do not appear on the screen as you type them.

See also:	Copying KP.EXE onto Your Computer's Hard Disk
Setting a Keyboard and Mouse Password


Copying KP.EXE onto Your Computer's Hard Disk

1.	Turn on your computer and allow POST to complete without error.

2.	Insert backup copy of System Utilities diskette into drive A.

3.	At MS-DOS prompt type a: then press [Enter] to access drive A.

4.	At A:\> prompt type copy kp.exe c: then press [Enter].

KP.EXE is then copied onto drive C of your computer's hard disk.

5.	Remove backup copy of System Utilities diskette.


Setting a Keyboard and Mouse Password

After copying KP.EXE onto your computer's hard disk, you can set a keyboard and mouse password using the following information.

1.	At MS-DOS prompt type kp then press [Enter].  You are then prompted to enter a password.

NOTE	Other applications, such as QEMM386 V6.01, use the character string kp to invoke or enable commands.  If you have such an application installed, add the /nic parameter when you want to set a keyboard and mouse password using the Keyboard Password utility.

2.	Enter a password then press [Enter].  You are then prompted to type password again to verify it.

3.	Enter password then press [Enter].  The keyboard has been locked.

4.	To unlock your keyboard, enter password and press [Enter].


Additional Diskettes and Device Drivers

MS-DOS/Windows, Windows NT,  Netware, & OS/2  NCR SCSI Drivers Diskette
NCR SCO UNIX SCSI Drivers Diskette

Refer to the supplied NCR SCSI Device Management System (SDMS) User's Guide for information on loading these device drivers for the following operating system software:

MS-DOS/Windows
Windows NT
Netware
OS/2
SCO UNIX


Configuring Your Computer

The information in the Help topics listed below explains how to configure your computer using the BIOS Setup utility.  If your computer was delivered with factory-installed software, it has already been configured.

If you are familiar with utility programs and their uses, refer to the material in the options table as you update your computer.  Otherwise, carefully read and understand all the information in both of these Help topics before attempting to modify your computer's configuration settings

See also:	Running the BIOS Setup Utility
Helpful Hints
BIOS Setup Utility Options


Running the BIOS Setup Utility

The BIOS Setup utility enables you to select and permanently store information about the computer's hardware and software in the batterybacked memory of the CMOS RAM.  This information takes effect each time the computer boots and can be changed each time you run setup.

Use the BIOS Setup utility if you experience problems with your hard disk or need to reconfigure your computer.  In addition, the BIOS Setup utility should be used to modify the configuration after you add or remove hardware, or change computer settings.

To run the BIOS Setup utility:

1.	Turn on your computer and allow POST to complete.

2.	Make a note of any configuration errors listed, and then press [F1] to display the first of three setup screens.

3.	Follow the instructions on your monitor screen and any on-line help pop-up screens to configure you computer.

Helpful Hints


Helpful Hints

•	Several keyboard function keys and numeric keypad keys are assigned to help you select menus and options, change option values, and display help information.  These keys are displayed at the bottom of each setup configuration screen.

•	On-line help pop-up screens are available at anytime during the setup process.  These screens provide information about highlighted options and, in some cases, offer suggestions on how to choose the correct field for a selected option.  To access these screens, highlight an option and press [F1].

•	Press [F2] to display important computer information.  Record all pertinent information.

•	Press [Esc] then press [F4] to exit the BIOS Setup utility and reboot your computer so changes immediately take effect.

•	Press [Esc] then press [F6] to exit the BIOS Setup utility without changes taking effect.

•	Press [Esc] then press [F5] to set all BIOS Setup utility options to their default values.


BIOS Setup Utility Options

NOTES TO OPTIONS TABLE

1	Drive type 48 or 49 information is aliased to drive type 2 or 3 when application software does not recognize drive types above 47
2	Auto-detection of IDE drive parameter is supported in types 2 and 3 and types 48 and 49
3	Some operating systems do not recognize hard disk drive types above 29
4	WB =  Write-Back; WT =  Write-Through
5	The options listed are applicable to slots 1, 2, and 3
6	Slot 2 allows IRQ14 instead of IRQ15.  IRQ14 must be used with any PCI/IDE expansion board
7	Slots 2 and 3 have master capability
NOTE	The language field in SETUP.EXE contains all the languages listed as possible settings.  The BIOS Setup utility does not.  The BIOS Setup utility choices are English and one other language.  For example, English and French, English and German, etc. depending on the language kit you ordered.

Setup Field	Settings	Comments
System time	Current time	Displays the current time
System date	Current date	Displays the current date
Language	English Français Deutsch Italiano Español Nederlands	The language field in SETUP.EXE contains all the languages listed as possible settings.  The BIOS setup utility choices are English and one other language. For example, English and French, English and German, depending on the language kit you ordered.
Diskette A / Diskette B	3.5", 1.44 MB 3.5", 2.88 MB Not Installed 5.25", 360 KB 5.25", 1.2 MB 3.5", 720 KB	Sets the size and density of diskette drives
Hard disk 1 / hard disk 2	Drive types 1 through 49	Enables hard drive size and specific parameters from a predetermined list of drive types.  Drive types 2 and 3 or 48 and 49 are user definable for hard drives not listed in the BIOS drive table(1)(2)
Base memory	640 KB/512 KB	displays the size of base (conventional) memory
Extended memory	Not user selectable	Displays the current amount of extended memory
Video card	VGA or EGA CGA 40 Column CGA 80 Column Monochrome Not Installed	Sets the video controller type
Keyboard	Installed Not Installed	Enables or disables the keyboard when using the computer as a network server Note You must initially setup your computer with a keyboard
NumLock on boot	On Off	Enables or disables the NumLock feature each time the computer boots
Password	Installed Not Installed	Enables a power-on password
ROM based setup	Enabled Disabled	Enables or disables the ROM base setup utility CAUTION If you select Disabled, make sure your computer is bootable and you have a working copy of SETUP.EXE provided on the supplied System Utilities diskette
Mouse port	Enabled Disabled	Enables the mouse port and assigns IRQ12 Disables the mouse port and frees up IRQ12 for option use
Parallel port	Enabled at: 378h-37Ah (IRQ7) Enabled at: 278h-27Ah (IRQ7) Enabled at: 3BCh-3BEh (IRQ7) Disabled Compatible mode Bi-directional mode	Enables or disables any desired onboard printer port at the specified address Allows you to select between standard printer and bi-directional applications
Serial port 1	Enabled at: 3F8h-3FFh (IRQ4) Enabled at: 2F8h-2FFh (IRQ3) Enabled at: 3E8h-2EFh (IRQ4) Enabled at: 2E8h-2EFh (IRQ3)	Enables or disables any desired onboard serial port at the specified address Note If your computer is connected to a network, see your System Administrator
Serial port 2	Enabled at: 2F8h-2FFh (IRQ3) Enabled at: 3E8h-3EFh (IRQ4) Enabled at: 2E8h-2EFh (IRQ3) Disabled Enabled at: 3F8h-3FFh (IRQ4)	Enables or disables any desired onboard serial port at the specified address Note If your computer is connected to a network, see your System Administrator
Diskette drive	Enabled Disabled	Enables or disables the onboard diskette drive controller
Exchange diskette drives	Disabled Enabled	Allows you to logically exchange physical diskette drive designations
Diskettes write protection	Disabled Enabled	Enables or disables the selected diskette drive's write protect option
IDE hard disk drives	Enabled Disabled	Enables or disables the onboard IDE disk drive controller
HDD user definable types	Types 2 and 3 Types 48 and 49	The BIOS Setup utility allows types 2 and 3 or types 48 and 49 to be user definable(3)
HDD data transfer method	Standard PIO Auto optimum	Allows for a standard, compatible data transfer method Allows the computer's BIOS to automatically set up the installed drive for optimum performance
Boot from diskette A	Enabled Disabled	Enables or disables drive A as the logical boot device
Boot from hard disk C	Enabled Disabled	Enables or disables drive C as the logical boot device
CPU speed	Fast Slow	Determines the speed used by your computer each time you turn it on or reboot
Primary cache	Enabled Disabled	Enables or disables your CPU's internal cache
Secondary cache	Enabled WT Enabled WB Disabled	Enables or disables your computer's external cache in WT or WB mode(4)
Cache BIOS ROM	Enabled Disabled	Allows you to enable or disable a caching request for your computer's BIOS
Shadow video ROM	Enabled Disabled	Enables or disables your computer's shadow video ROM option
Cache video ROM	Enabled Disabled	Enables or disables your computer's cache video ROM option
Shadow 32K at C8000	Enabled Disabled	Enables or disables your computer's C8000 shadow option
Shadow 32K at D0000	Enabled Disabled	Enables or disables your computer's D0000 shadow option
Shadow 32K at D8000	Enabled Disabled	Enables or disables your computer's D8000 shadow option
AT bus space	Disabled F80000h, .5MB F00000h, 1MB E00000h, 1MB E00000h, 2MB C00000h, 4MB	Not used Sets the memory hole at address F80000 with a  .5 MB memory size Sets the memory hole at address F00000 with a  1 MB memory size Sets the memory hole at address E00000 with a  1 MB memory size Sets the memory hole at address E00000 with a  2 MB memory size Sets the memory hole at address C00000 with a  4 MB memory size
512KB-640 KB mapping	Main memory PCI/ISA	Allows you to map the  memory region between 512KB to 640KB to your computer's main memory Allows you to map the  memory region between 512KB and 640KB to the PCI or ISA bus
Onboard PCI SCSI	Enabled Disabled	Enables or disables the onboard SCSI controller
External SCSI device	Enabled Disabled	Enables or disables your main logic board's external SCSI port by enabling or disabling the termination of external SCSI bus on the main logic board
PCI device(5)	Enable device:    Enabled    Disabled Device IRQ:    None    IRQ5    IRQ9    IRQ10    IRQ15(6)    IRQ14(6) Enable master:(7)    Enabled    Disabled Latency timer    Default      . . . .	Allows you to individually enable or disable each PCI slot Allows you to individually set an IRQ default for each PCI slot Allows you to enable or disable a PCI device that requires master capability Allows you to set the PCI latency timer (in PCI clocks) for each PCI device


Base memory

The main logic board reserves the first 1024 KB of address space for computer use.  Base memory (640 KB) is first assigned to the operating system.  The remaining 384 KB is assigned to shadow main logic board BIOS, video BIOS, or for other computer use.

Base memory can be modified using the 512KB-640KB mapping field.


ROM based setup

This option is often used by educational facilities that have public access to their computers.  Disabling this option prevents unauthorized personnel from changing any computer's configuration parameters.


Password

This option allows you to enable a power-on password.

If you need to change or remove a power-on password, follow these procedures:

To change the power-on password, at the password prompt, type oldpassword/newpassword

To remove the power-on password, at the password prompt, type oldpassword/


Parallel port and serial ports

Your computer logically assigns LPTx and COMx names to:

•	Parallel ports in the address order 378h and 278h

•	Serial ports in the address order 3F8h, 2F8h, 3E8h, and 2E8h

This occurs during each boot process.  For example, if you disable the serial port that is assigned to 3F8h as COM1, during the next boot cycle the computer reassigns the name COM1 to the next enabled serial port in the sequence.


CPU speed

This option determines the speed used by the computer each time you turn it on or reboot it.

•	Fast—is the normal speed and causes the CPU to run at its rated speed.

•	Slow—(equivalent to 8 MHz) is used to reduce the effective CPU speed to be compatible with some speed-dependent application programs.

If an application program does not run correctly at full speed, try disabling all caches or changing the CPU speed to slow.

⇒	Computer performance will be severely degraded while operating in slow mode.


HDD data transfer method

This option lets you take advantage of new IDE hard disk drive technologies.   Setting this option to Auto Optimum allows your computer's BIOS to interrogate and automatically set up any installed IDE hard disk drive for optimum performance.


Primary cache

This option lets you enable or disable the microprocessor's internal (primary) cache.  Enabling the cache controller significantly improves computer performance by reducing the average number of wait states seen by the microprocessor.

However, in some instances you might want to disable the primary cache, for example, while using time-dependent software.  In this instance, the computer can operate but not at full potential.


Secondary cache

This option lets you enable or disable the computer's external (secondary) cache.  Enabling the secondary cache significantly improves computer performance by reducing the average number of wait states seen by the microprocessor.

However, in some instances, you might want to disable the secondary cache, for example, while using time-dependent software.  In this instance, the computer can operate but not at full potential.

Also, this field can be set to either Write-Back or Write-Through mode.

CAUTION	If your computer contains a Pentium CPU module, ensure that this option is set to Write-Through mode.

NOTE	If you do not have any secondary cache installed, make sure this option is set to disabled.


Cache BIOS ROM

This option allows the computer's BIOS to be cached in the primary cache and secondary cache (if installed).  This increases computer performance because BIOS instructions are executed in cache instead of RAM.


Shadow video ROM

The main logic board reserves an area of DRAM for a copy of video BIOS ROM.  This DRAM called "shadow memory" is write-protected and has the same addresses as the video BIOS ROM locations.  When you shadow video BIOS ROM, the ROM information is copied into an appropriate area in DRAM.  This increases your computer's performance because the video BIOS instructions are in fast DRAM instead of ROM.


Cache video ROM

This option allows your computer to cache video BIOS information.  Caching your computer's video ROM provides greater performance at the VGA level, however, when running certain application software, conflicts might occur.


Shadow 32K at C8000, D0000, and D8000

These options allow your computer to shadow any device BIOS located in the C8000 to DFFFF address space.  Shadowing device BIOS in these areas increases your computer's overall performance.


AT bus space

This option allows additional space in the 1 MB to 16 MB address range to be mapped to the PCI or ISA bus.  Exercising this option creates a memory hole and maps the physical memory that was addressed to the region to the top of main memory.


512KB-640KB mapping

This option allows the address space between 80000 and 9FFFF to be mapped to the PCI or ISA bus.  Note that when this option is enabled, the amount of conventional memory under MS-DOS is reduced by 128 KB.


PCI device

This option allows you to configure the three PCI slots on your computer's main logic board.

CAUTION	The PCI Device selections should stay at the factory default settings unless they absolutely need to be modified.  Needless modifications can cause computer failure.


BIOS

Basic Input/Output System


flash memory

Allows you to retrieve or update your computer's BIOS via software.


PCI local bus

Peripheral Component Interconnect (PCI) Local Bus delivers maximum computer performance by providing a wider data path, greater speed, and improved expandability.


recovery diskette

A recovery diskette should always be prepared before attempting to upgrade the BIOS.  This diskette contains a BIOS image and a program to load the image into flash memory.


SCSI controller

Your computer uses an embedded SCSI controller that automatically controls SCSI peripherals.  It can also function as a secondary peripheral controller if your computer already uses a primary disk drive controller (such as IDE).


SETUP.EXE

Digital recommends that you use SETUP.EXE on the System Utilities diskette only when you need to enable the ROM Based Setup option.  Otherwise, use the BIOS Setup utility.


ZIF

Zero Insertion Force.  A ZIF socket allows you to easily upgrade your system board by adding a higher performance CPU chip.


Related Material

DECpc XL Series Installation Card	ER-770WW-IA
DECpc XL Series User's Guide	ER-770WW-UA
DECpc XL Series Service Guide	ER-770WW-SA
DECpc 928 PCI Bus Video Adapter User's Guide	ER-XAGAK-UA
DECpc Pentium/PCI Series CPU Module	ER-780WW-CM
DECpc i486/PCI CPU Module	ER-772WW-CA
NCR SCS Device Management System User's Guide	ER-770WW-AA.A01


Glossary

512KB-640KB mapping

AT bus space

Base memory

BIOS

Cache BIOS ROM

Cache video ROM

computer battery/real time clock:

CPU module

CPU speed

flash memory

HDD data transfer method

new screws

Parallel port and serial ports

PCI device

Primary cache

Recovery diskette

ROM based setup

Secondary cache

Shadow 32K at C8000, D0000, and D8000

Shadow video ROM

SIMM

static electricity

ZIF


Expanding Your Computer

Introduction

Tools Needed

Before You Begin

FRU List (Part Numbers)

Computer Components

Connecting Devices in Upper Drive Bay Area

Disconnecting Power Supply

Removing On/Off Switch

Removing Power Plug

Removing Power Supply

Expansion Brackets

Main Logic Board

Mass Storage Devices

Installing Additional Computer Memory

Memory Configurations (Pentium)

Memory Configurations (i486)

Installing Additional Secondary Cache Memory (i486)

Installing Devices in Lower Drive Bay Area

Installing Devices in Upper Drive Bay Area

Installing Expansion Boards

Installing SIMMs

Replace Computer Battery/Real Time Clock (RTC)

Removing CPU Chip (Pentium or i486)

Removing CPU Module

Removing Fan Pipe

Removing Fan/Speaker Assembly

Removing Lower Drive Bay Assembly

Removing Main Logic Board

Unlocking  and Removing Side Panels


Introduction

The following information will help you install, replace, or modify the following hardware:

•	CPU module

•	Main logic board options:

Memory

Real-time clock (RTC) (computer battery)

•	Optional ISA and PCI local bus expansion boards

•	Mass storage devices


Tools Needed

The following tools are recommended:

•	A Phillips screwdriver

•	An antistatic wrist strap (highly recommended, but not required)

WARNING	See also	Static Electricity


Before You Begin

Before removing side panels, do the following:

1.	Turn off power to all external devices connected to computer.

2.	Turn computer off.

3.	Unplug power cord from wall outlet.

4.	Disconnect power cord and monitor cord from computer.

WARNING	See also	Static Electricity


Unlocking and Removing Side Panels

WARNING	You might injure yourself or damage your computer if you attempt to remove side panels before unplugging ac and monitor power cords.

1.	Remove computer from pedestal, if applicable.

2.	Turn key clockwise to unlock side panels.

3.	Slide panels to rear of computer.


Computer Components

Click on any highlighted letter or check the Legend to see information about the corresponding portion of the illustration.

Legend

A	Power supply

B	4 ISA and 2 PCI 32-bit local bus expansion slots or
3 ISA and 3 PCI 32-bit local bus expansion slots

C	CPU module

D	Main logic board

E	3½-inch diskette drive

F	Three 5¼-inch half-height drive bays

G	Hidden 3½-inch half-height drive bay


168-2A

A	Power supply


168-2B

B	4 ISA and 2 PCI 32-bit local bus expansion slots or
3 ISA and 3 PCI 32-bit local bus expansion slots


168-2C

C	CPU module


168-2D

D	Main logic board


168-2E

E	3½-inch diskette drive


168-2F

F	Three 5¼-inch half-height drive bays


168-2G

G	Hidden 3½-inch half-height drive bay


Main Logic Board

Click on any highlighted letter or check the Legend to see information about the corresponding portion of the illustration.

Legend

A	Power supply connection

B	Diskette drive connection

C	Mouse and keyboard connections

D	Serial port connections

E	External SCSI and parallel port connections

F	3 ISA expansion slots

G	Flash BIOS

H	Dedicated CPU module connector

I	Real-time clock/computer battery

J	Six 36-bit SIMM sockets

K	IDE drive connector

L	Internal SCSI connection

M	3.3 V power connection

N	2 PCI expansion slots

O	1 ISA and 1 PCI expansion slot (only one slot used at any one time)

P	6-pin PCB header (for additional power supply connection)


167-3A

A	Power supply connection


167-3B

B	Diskette drive connection


167-3C

C	Mouse and keyboard connections


167-3D

D	Serial port connections


167-3E

E	External SCSI and parallel port connections


167-3F

F	3 ISA expansion slots


167-3G

G	Flash BIOS


167-3H

H	Dedicated CPU module connector


167-3I

I	Real-time clock/computer battery


167-3J

J	Six 36-bit SIMM sockets


167-3K

K	IDE drive connector


167-3L

L	Internal SCSI connection


167-3M

M	3.3 V power connection


167-3N

N	2 PCI expansion slots


167-3O

O	1 ISA and 1 PCI expansion slot (only one slot used at any one time)


167_3P
167-3P

P	6-pin PCB header (for additional power supply connection)


Installing Additional Computer Memory

Adding more memory allows your computer to run larger, more complicated software and run it quicker.

The amount of memory your computer supports depends on the type of CPU module you have installed.  If you have an i486 PCI Series CPU module installed, your computer will support up to 128 MB using SIMM banks 0 through 3 only.  If you have the Pentium PCI Series CPU module installed, your computer will support up to 192 MB using SIMM banks 0 through 5.

CAUTION	If you plan on operating your computer with 64 MB or more of memory and you have the i486 PCI Series CPU module installed, you must install an additional 128 KB of secondary cache.  Failure to do so can cause computer failure.  An additional 128 KB cache memory option is available from Digital to increase secondary cache memory to 256 KB.  This kit consists of four 32 MB x 8 SRAM chips installed in DIP sockets on the CPU module.

Your computer comes with at least 8 MB of memory.  You can add 4 MB, 16 MB, or
32 MB SIMMs.  The computer requires 36-bit SIMMs that have an access time of 70 ns or less.

See also:	Memory Configurations (i486)
Memory Configurations (Pentium)
Installing SIMMs


Memory Configurations (i486)

The allowable memory configurations for the i486 PCI Series CPU Module are:

i486 PCI Series CPU Module Installed

Bank 0	Bank 1	Bank 2	Bank 3	Total
4 MB	4 MB			8 MB
4 MB	4 MB	4 MB	4 MB	16 MB
8 MB	8 MB			16 MB
4 MB	4 MB	8 MB	8 MB	24 MB
8 MB	8 MB	8 MB	8 MB	32 MB
16 MB	16 MB			32 MB
4 MB	4 MB	16 MB	16 MB	40 MB
8 MB	8 MB	16 MB	16 MB	48 MB
16 MB	16 MB	16 MB	16 MB	64 MB
32 MB	32 MB			64 MB
4 MB	4 MB	32 MB	32 MB	72 MB
8 MB	8 MB	32 MB	32 MB	80 MB
16 MB	16 MB	32 MB	32 MB	96 MB
32 MB	32 MB	32 MB	32 MB	128 MB


Memory Configurations (Pentium)

The allowable memory configurations for the Pentium PCI Series CPU Module are:

Pentium PCI Series CPU Module Installed

Bank 0	Bank 1	Bank 2	Bank 3	Bank 4	Bank 5	Total
4 MB	4 MB					8 MB
4 MB	4 MB	4 MB	4 MB			16 MB
8 MB	8 MB					16 MB
4 MB	4 MB	4 MB	4 MB	4 MB	4 MB	24 MB
4 MB	4 MB	8 MB	8 MB			24 MB
4 MB	4 MB	4 MB	4 MB	8 MB	8 MB	32 MB
8 MB	8 MB	8 MB	8 MB			32 MB
16 MB	16 MB					32 MB
4 MB	4 MB	8 MB	8 MB	8 MB	8 MB	40 MB
4 MB	4 MB	16 MB	16 MB			40 MB
8 MB	8 MB	8 MB	8 MB	8 MB	8 MB	48 MB
8 MB	8 MB	16 MB	16 MB			48 MB
4 MB	4 MB	8 MB	8 MB	16 MB	16 MB	56 MB
16 MB	16 MB	16 MB	16 MB			64 MB
32 MB	32 MB					64 MB
4 MB	4 MB	32 MB	32 MB			72 MB
4 MB	4 MB	16 MB	16 MB	16 MB	16 MB	72 MB
4 MB	4 MB	4 MB	4 MB	32 MB	32 MB	80 MB
8 MB	8 MB	16 MB	16 MB	16 MB	16 MB	80 MB
8 MB	8 MB	32 MB	32 MB			80 MB
4 MB	4 MB	8 MB	8 MB	32 MB	32 MB	88 MB
8 MB	8 MB	8 MB	8 MB	32 MB	32 MB	96 MB
16 MB	16 MB	16 MB	16 MB	16 MB	16 MB	96 MB
16 MB	16 MB	32 MB	32 MB			96 MB
8 MB	8 MB	16 MB	16 MB	32 MB	32 MB	112 MB
32 MB	32 MB	32 MB	32 MB			128 MB
16 MB	16 MB	16 MB	16MB	32 MB	32 MB	128 MB
4 MB	4 MB	32 MB	32 MB	32 MB	32 MB	136 MB
8 MB	8 MB	32 MB	32 MB	32 MB	32 MB	144 MB
16 MB	16 MB	32 MB	32 MB	32 MB	32 MB	160 MB
32 MB	32 MB	32 MB	32 MB	32 MB	32 MB	192 MB


Installing Additional Secondary Cache Memory (i486)

The i486/PCI CPU module is equipped with 128 KB direct-mapped adaptive write-back secondary cache memory.  This memory is designed to improve the performance of the installed CPU.

An additional 128 KB cache memory option, in the form of a kit containing four 2ns 32 KB x 8 SRAM chips, is available to increase the secondary cache memory to 256 KB.

CAUTION	If your computer contains 64 MB or more of memory, you must install this additional 128 KB of secondary cache.  Failure to do so can cause computer failure.

Handle secondary cache memory chips carefully, holding them only by their edges.

Make sure each SRAM chip's pin 1 location is properly aligned with the pin 1 location on the socket (see illustration).  Improper installation can cause faulty computer operation.

To install additional secondary cache memory:

1.	Remove the CPU module and place it on an anti-static surface.

2.	Locate the secondary cache memory DIP sockets.

3.	Insert each chip into the appropriate DIP socket.


Installing SIMMs

CAUTION	Use care when installing SIMMs. The retaining clips on the sockets break easily if the SIMM is not seated correctly.

1.	Turn off your computer.

2.	Disconnect external devices, ac power, and monitor power.

3.	Unlock and remove left side panel.

4.	Install SIMM into socket at a 45 degree angle.

Make sure notch is oriented as shown.  Rock SIMM gently until it seats evenly into  bottom of socket.  Tip SIMM upright until both retaining clips engage.

5.	Replace and lock left side panel.

6.	Connect external devices and restore power.

7.	Run BIOS Setup utility to configure computer for additional memory.

See also:	Configuring Your Computer


Replace Computer Battery/Real Time Clock (RTC)

To replace the computer battery/real time clock:

1.	Turn off your computer.

2.	Disconnect external devices, ac power, and monitor power.

3.	Unlock and remove left side panel.

4.	Remove battery.

5.	Install new battery.

CAUTION	Make sure pin 1 on battery is correctly aligned with location on socket (see figure).  Incorrect installation can cause faulty computer operation.

6.	Replace and lock left side panel.

7.	Connect external devices and restore power.

8.	Run BIOS Setup utility to configure computer.

See also:	Configuring Your Computer


Installing Expansion Boards

Your DECpc XL Series computer contains seven expansion board slots as shown.  Four of the slots support industry-standard 16-bit ISA expansion boards.  The remaining three PCI local bus expansion slots support 32-bit PCI local bus expansion boards.  This allows your computer to deliver maximum performance by using a wider data path for greater computing speed and improved expandability.

Click on any highlighted letter or check the Legend to see information about the corresponding portion of the illustration.

NOTE	Only one expansion board can reside in slot J6 and J13 at any one time. These slots have to share the expansion slot opening at the rear panel.

NOTE	Read and fully understand your optional expansion board's documentation before installing it.

To install an ISA or PCI local bus expansion board:

1.	Turn off your computer.

2.	Disconnect external devices, ac power, and monitor power.

3.	Unlock and remove left side panel.

4.	Unscrew and remove the metal filler panel for the desired expansion slot.

5.	Insert new expansion board into socket.

Push expansion board firmly into place.

6.	Secure expansion board to slot.

7.	Replace and lock left side panel.

8.	Connect external devices and restore power.

Legend

J7, J8, J9	ISA	Supports industry-standard 16-bit ISA expansion boards

J6	ISA	Supports industry-standard 16-bit ISA expansion boards

Designated as a shared slot with PCI slot J13 (see NOTE)

J11/PCI slot 1	PCI	Supports non-bus mastering 32-bit PCI expansion boards

Digital recommends that you install your 32-bit PCI video adapter in this slot

J12/PCI slot 2	PCI	Supports non-bus or bus mastering 32-bit PCI expansion boards

Digital recommends that you install 32-bit bus mastering PCI expansion boards in this slot

J13/PCI slot 3	PCI	Supports bus mastering or non-bus mastering 32-bit PCI expansion boards

Designated as a shared slot with PCI slot J6 (see NOTE)


167-5A

J7, J8, J9	ISA	Supports industry-standard 16-bit ISA expansion boards


167-5B

J6	ISA	Supports industry-standard 16-bit ISA expansion boards

Designated as a shared slot with PCI slot J13 (see NOTE)


167-5C

J11/PCI slot 1	PCI	Supports non-bus mastering 32-bit PCI expansion boards

Digital recommends that you install your 32-bit PCI video adapter in this slot


167-5D

J12/PCI slot 2	PCI	Supports non-bus or bus mastering 32-bit PCI expansion boards

Digital recommends that you install 32-bit bus mastering PCI expansion boards in this slot


167-5E

J13/PCI slot 3	PCI	Supports bus mastering or non-bus mastering 32-bit PCI expansion boards

Designated as a shared slot with ISA slot J6 (see NOTE)


Mass Storage Devices

Your computer has two drive bay areas that can have hard disk drives, floppy diskette drives, CD-ROM drives, and tape backup systems installed in them.


Upper drive bay area

This area has room for three 5¼-inch half-height devices.  Each drive bay is equipped with a removable panel to accommodate devices requiring front panel access.

The bottom two bays of this area can be used to mount one full-height drive.  The drive rails are removable to accommodate a full-height device.


Lower drive bay area

This area has a drive bay assembly that holds a 3½-inch floppy diskette drive (standard on all DECpc XL series computers) and one hidden 3½-inch half-height device that needs no front panel access.  This hidden bay is typically used for mounting the computer's primary 1-inch or 1.6-inch hard disk drive.


Expansion Brackets

You can install half-height devices in any of the three positions in the upper drive bay area.  To install a 3½-inch device in the upper drive bay, you must first install expansion brackets.  Expansion brackets are either supplied with the device or can be purchased from Digital.  Contact your local Digital representative for additional information.


Installing Devices in Upper Drive Bay Area

1.	Turn off your computer.

2.	Disconnect external devices, ac power, and monitor power.

3.	Unlock and remove both side panels.

4.	Remove plastic filler panel.

5.	Insert new device.

 	See also:	Connecting Devices in Upper Drive Bay Area
Thermal Considerations


Connecting Devices in Upper Drive Bay Area

Click on any highlighted letter or check the Legend to see information about the corresponding portion of the illustration.

Sample IDE Configuration	Sample SCSI Configuration

1.	Connect the ribbon cable to the device as shown.

Make sure cable is connected with correct orientation.  Most cables and sockets are keyed so that you cannot connect them backwards.  If your cable or device are not keyed, you must connect pin 1 of cable to pin 1 of device's socket.

Pin 1 of cable is on edge with colored stripe.  Pin 1 of device's socket should be marked with a tiny number "1" at one end of socket or with a tiny number "1" printed on circuit board near one end of socket.

2.	Connect power cable to device.  Use a 4-pin connector from power supply.

3.	Secure device with two screws on each side.  Use screws that came with device.

4.	If device is an internal device with no front panel, replace plastic filler panel.

5.	Replace and lock both side panels.

6.	Connect external devices and restore power.

7.	Run BIOS Setup utility to configure computer.

See also:	Configuring Your Computer

Legend

IDE	SCSI

A	Power supply	A	Power supply

B	Power connections	B	Power connections

C	Diskette drive connection	C	Internal SCSI cable

D	IDE Drive connection	D	SCSI connector

E	Diskette drive	E	SCSI hard disk drive

F	Hard drive	F	CD-ROM drive (or other SCSI device)

G	Optional storage devices


169A

A	Power supply


169B

B	Power connections


169C

C	Diskette drive connection


169D

D	IDE Drive connection


169E

E	Diskette drive


169F

F	Hard drive


169G

G	Optional storage devices


182A

A	Power supply


182B

B	Power connections


182C

C	Internal SCSI cable


182D

D	SCSI connector


182E

E	SCSI hard disk drive


182F

F	CD-ROM drive (or other SCSI device)


Removing Lower Drive Bay Assembly

CAUTION	Make sure you support drive bay assembly so that it does not fall and damage circuit boards.

1.	Turn off your computer.

2.	Disconnect external devices, ac power, and monitor power.

3.	Unlock and remove left side panel.

4.	Remove cables from devices in lower drive bay.

Note cable positions so you can properly connect the devices later.

5.	Depress retaining clip at rear-top of drive bay assembly while sliding assembly to rear of computer.


Installing Devices in the Lower Drive Bay Area

1.	Remove lower drive bay assembly.

2.	Remove old device by removing screws on its side and by sliding it out of lower bay assembly.

3.	Slide new device into drive bay assembly and secure using new screws.

4.	Replace lower drive bay assembly by sliding it forward until retaining clip latches.

5.	Connect any data and power cables to devices.

6.	Replace and lock left side panel.

7.	Connect external devices and restore power.

8.	Run BIOS Setup utility to configure computer.

See also:	Configuring Your Computer


Removing Fan/Speaker Assembly

1.	Remove fan and speaker connections.

2.	Depress tabs.

3.	Pull forward.


Removing Main Logic Board

1.	Remove all connectors.

2.	Remove all expansion boards.

3.	Remove fan/speaker assembly.

4.	Remove lower drives.

5.	Loosen screws and slide off standoffs.


Removing CPU Chip (Pentium or i486)

Pentium	i486

1.	Release the lever.

2.	Remove the chip.

CAUTION	Before installing a new CPU module, .update your computer BIOS.  Do not wait to update the BIOS until after installing a new CPU module.


179-2A

Pin 1


Removing CPU Module

1.	Remove retaining bracket.

2.	Pull CPU module from slot.

CAUTION	Before installing a new CPU module, .update your computer BIOS.  Do not wait to update the BIOS until after installing a new CPU module.


Removing Fan Pipe

1.	Push in on retaining clip.

2.	Release fan pipe from fan assembly.


Disconnecting Power Supply

Before removing the power supply from the computer, you must be sure that the on/off switch and power plug have been removed.

Removing On/Off Switch

Removing Power Plug

Removing Power Supply


Removing On/Off Switch

This step must be performed prior to removing the power supply.

1.	Remove CPU module.

2.	Remove connections.

3.	Remove upper and lower drives.

4.	Remove on/off switch.

Continue preparing to remove the power supply by
Removing Power Plug


Removing Power Plug

This step must be performed prior to removing the power supply.

1.	Be sure that the on/off switch has been removed.

2.	Remove screw from power plug.

3.	Pull out power plug.

You are now ready to remove the power supply itself.
Removing Power Supply


Removing Power Supply

1.	Be sure that the on/off switch and power plug have been removed.

2.	Remove four screws from the rear.

3.	Slide power supply forward and out.


computer battery/real time clock:
computer battery/real time clock

Runs the computer clock and retains any setup information when it is turned off.


CPU module

If you plan on replacing your CPU module, upgrading your CPU module's CPU, or adding additional secondary cache memory refer to the appropriate CPU Specifications Booklet supplied with your computer.


new screws

Do not use old screws.  They might be too long and, as a result, can damage your device's internal mechanisms.


SIMM

Single In-line Memory Module


static electricity

Static electricity collects on non-conductors such as paper, cloth, or plastic and can be so small that you cannot see or feel it.

To prevent damage to circuit boards and/or components:

•	Before touching any circuit board or component, touch the metal frame of your computer to discharge any static electricity.

•	Keep circuit boards and components away from non-conductors.

•	Keep clothing away from circuit boards and components.

•	Keep circuit boards in anti-static bags.


FRU List (Part Numbers)

Part #	Description

17-00083-54	Power cord, term 125v
17-00209-15	Power cord, term 250v
17-03460-03	Flat cable, 34-pin (diskette drive)
17-03461-03	Flat cable, 40-pin (IDE drive)
17-03779-01	Keyboard extension cable, 3 ft.
21-33453-02	CPU, 486DX/33
21-39004-02	CPU, 486DX2/66
21-40460-01	CPU, P5/60
21-40460-02	CPU, P5/66
  -ME534-HE	8MB x 2, SIMM, 70ns (54-21246-EA * 2)
  -ME644-FE	16MB x 2, SIMM, 70ns (54-23170-AA * 2)
  -ME654-HE	32MB x 2, SIMM, 70ns (54-21277-AA * 2)
  -PC77M-CA	1MB VRAM, 70ns, SOIC, VGA memory
  -PCXAL-NA	Keyboard, US
  -PCXAR-AL	SCSI HDD, 1 GB (1.6" high)
  -PCXAR-AH	SCSI HDD, 525 MB
  -PCXAR-CG	3.5" HDD, 525 MB (IDE)
  -PCXAR-CH	3.5" HDD, 170 MB (IDE)
  -PCXAR-CJ	3.5" HDD, 340 MB (IDE)
  -RE23Q-EA	3.5" HDD 170 MB (multi pack)
  -RE24M-E	3.5" HDD 340 MB (multi pack)
  -RX26 -AA	3.5" FDD, 2.88 MB
  -RZ25L-E	3.5" SCSI HDD 525 MB (multi pack)
  -RZ26 -L	SCSI HDD, 1 GB (multi pack)
30-32969-02	3.5" FDD, 1.44 MB
30-33156-02	5.25" FDD, 1.2 MB
54-22697-01	CPU Module, 486DX/33 w/128K cache
54-22697-02	CPU Module, 486DX2/66 w/128K cache
54-22697-03	CPU Module, 433DX/466D2 w/128K cache (CPU card w/o CPU)
54-22699-01	928 PCI video adapter card
54-22701-01	CPU Module, PCI/ISA, 486 main board
54-22701-02	CPU Module, PCI/ISA, P5 main board
70-30805-01	pedestal assembly
70-31627-01	CPU Module, P5/60 w/256K cache
70-31627-03	CPU Module, P5/60/66 (CPU card w/o CPU)
74-46480-01	exchange, 3.5" drive (option)
74-46507-01	cover, 3.5" FDD exchange (option)
74-46508-01	cover, 3.5" drive (option)
74-46548-01	pedestal bail
ER-XAGAK-UA	DECpc 928 PCI Bus VGA User's Guide
QB-0QRAA-SB	Windows NT software kit
QB-00CAA-HB	QAPlus software kit
QB-MESAA-SA	MS-DOS/Windows software kit (English)
QC-01CAA-HC	S3 928/PCI VGA Utilities & Drivers
QC-01DAA-HC	DECpc 486 Series System Utility
QC-01EAA-HC	DECpc XL Pentium Series System


Problem Solving and Troubleshooting

These topics provide initial troubleshooting procedures and tables listing specific problems, probable causes, and recommended actions to take if your computer fails after you configure it or after you install optional hardware or software.

Refer to the documentation supplied with additional options if you are experiencing problems with specific options that you have installed.

Initial Troubleshooting

Computer Troubleshooting

Disk Drive Troubleshooting

Monitor Troubleshooting

See also:	Computer Messages


Initial Troubleshooting

Follow these general procedures to troubleshoot your DECpc XL Series computer.

Press [Ctrl] + [Alt] + [Del].  If your computer fails to boot, turn it off, wait 20 seconds, and then turn it back on.

Ensure that all cables and connections are secure.

If the POST detects an error refer to Computer Messages and take the appropriate steps to correct the problem.  After the problem has been resolved, restart the computer.

Run the diagnostic software.

Run the BIOS Setup utility.

Contact Digital Services for software or hardware related problems.

See also:	 Configuring Your Computer

NOTE	If you need to return a failed component, pack it in its original container and return it to Digital for service.

If you are a self-maintenance customer, call your Digital service representative for assistance and recommendations.


Computer Troubleshooting

Problem	Possible Cause	Action
No response when the computer is turned on.	Computer is not plugged in. No power at the wall outlet. Main logic board  failure. Main logic board jumpers incorrectly set. CPU module failure. CPU module  jumpers incorrectly set.	Turn off the computer, plug it in, and then turn it back on again. Use another wall outlet. Replace main logic board. Set all appropriate jumpers. Replace main logic board. Make sure the jumpers are correctly set
Power is on, but there is no screen display.	Brightness and contrast controls are not correctly set. Monitor is off.	Adjust the brightness and contrast controls. Turn on the monitor.
	Monitor cable is incorrectly installed. Video adapter not seated in the expansion slot correctly. Video adapter has failed.	Check all monitor connections. Reseat the video adapter. Replace video adapter.
Computer does not boot from an IDE hard disk drive.	Operating system software is not installed on the IDE hard disk drive. IDE hard disk drive is not correctly formatted or the requested partition does not exist. There is no software on the requested partition. IDE hard disk drive jumpers incorrectly set. IDE drive type incorrect. Loose cables. Onboard IDE interface disabled. "Boot from Hard Disk C" is disabled via BIOS Setup utility.	Install the appropriate operating system. Format the IDE hard disk drive or partition the IDE hard disk drive using the supplied operating system software. Install software on the requested partition. Refer to the supplied IDE hard disk drive kit installation instructions. Run the BIOS Setup utility to identify the correct drive type. See drive type label on drive or consult drive documentation. Secure all cable connections. Run the BIOS Setup utility and set the IDE Hard Disk Drives option to "Enabled." Enable the "Boot from Hard Disk C" via BIOS Setup utility.
Computer does not recognze an internal SCSI device.	Onboard SCSI device disabled.	Enable the Onboard PCI SCSI setup field using the BIOS Setup utility.
	SCSI device jumpers incorrectly set.	Refer to the supplied SCSI device kit installation instructions.
	SCSI ID conflicts.	Refer to the supplied SCSI device kit installation in-structions on setting SCSI IDs.
	Terminating resistors not removed from the SCSI device.	Remove terminating resistors. Refer to the supplied kit installation instructions.
	SCSI cable not terminated.	Terminate each end of the SCSI cable.
Computer does not recognize an external SCSI device.	External SCSI port disabled.	Run the BIOS Setup utility and set the External SCSI Device option to "Enabled."
	SCSI device jumpers incorrectly set.	Refer to the supplied SCSI device kit installation instructions.
	SCSI ID conflicts.	Refer to the supplied SCSI device kit installation in-structions on setting SCSI IDs.
	Terminating resistors not removed from the SCSI device.	Remove terminating resistors. Refer to the supplied kit installation instructions.
	SCSI cable not terminated.	Terminate each end of the SCSI cable.
Computer does not boot from an internal SCSI hard disk drive.	Operating system software is not installed on the SCSI hard disk drive. Requested partition does not exist. Computer not configured for SCSI hard disk drive operation.	Install the appropriate operating system. Partition the SCSI hard disk drive and then reload the operating software. Run the BIOS Setup utility and set Hard Disk 1/Hard Disk 2 to "Not Installed" and IDE Hard Disk Drives options to "Disabled."  This disables the onboard IDE interface. NOTE If you have both IDE and SCSI hard disk drives installed, your computer uses the IDE hard disk drive as the boot device.
Computer does not boot from a target diskette drive.	Drive ID incorrectly set. Diskette drive not enabled. Diskette boot option disabled. Diskette does not contain start-up files. Diskette drive is empty. Diskette is worn or damaged. Loose cables.	Make sure the drive ID is correctly set (refer to the documentation supplied with your diskette drive). Run the BIOS Setup utility to enable the diskette drive. Run the BIOS Setup utility and set Boot From Diskette A to "Enabled." Insert a diskette with the correct start-up files. Insert a diskette that contains an operating system. Try another diskette. Secure all cable connections.
No response to keyboard commands.	Keyboard is password protected. Keyboard is not connected. Keyboard is connected to the mouse port.	Enter the keyboard password. Power down the computer and connect the keyboard. Power down the computer and connect the keyboard to the keyboard port.
No response to mouse commands.	Mouse port is disabled. Mouse is password protected. Mouse is not connected. Mouse is connected to the keyboard port. Mouse driver not installed.	Enable mouse port using BIOS Setup utility. Enter the keyboard and mouse password. Power down the computer and connect the mouse. Power down the computer and connect the mouse to the mouse port. Install the appropriate mouse driver.  Refer to your supplied application software documentation.


Disk Drive Troubleshooting

Problem	Possible Cause	Action
IDE/SCSI hard disk drive cannot read or write information.	Incorrect disk drive jumper settings. Loose or incorrectly installed cables. IDE/SCSI hard disk drive is not correctly formatted or partitioned. IDE drive type incorrect.	Refer to the supplied kit installation instructions. Make sure all cables are correctly installed. Format and partition as required using the supplied operating system. Run the BIOS Setup utility to identify the correct drive type.
Target diskette drive cannot read or write information.	Diskette is not formatted. Diskette is worn or damaged. Diskette is write-protected. Diskette drive is empty. Diskette write protection enabled.	Format the diskette. Try another diskette. Slide the write-protect switch so the hole is not visible (3½-inch diskette) or uncover the writeprotect notch (5¼-inch diskette). Insert a diskette. Run the BIOS Setup utility and set the Diskette Write Protection option to "Disabled."


Monitor Troubleshooting

Problem	Possible Cause	Action
Monitor power indicator is not on.	Monitor is turned off. Power cord is not connected. No power at wall outlet. Power indicator is defective.	Turn on the monitor. Connect the power cord to the computer. Use another outlet. Replace power indicator.
No screen display.	Monitor power cable is loose or disconnected. Configuration error. Monitor brightness and contrast controls are incorrectly set.	Secure or reattach the monitor power cable. Run the BIOS Setup utility to configure the computer for VGA operation. Set the jumper for VGA operation.  Refer to Appendix B. Adjust the monitor brightness and contrast controls.
No monitor display while loading Windows video drivers.	Monitor type incorrectly set.	Set the correct monitor type using the appropriate utility.  Refer to an appropriate Video Adapter User's Guide or the 928/PCI Video Adapter Help topics.
Distorted, rolling, or flickering screen display, or wrong/uneven color.	Monitor incorrectly adjusted. Monitor signal cable incorrectly installed.	Adjust accordingly. Straighten any bent connector pins and then reconnect.
Color monitor displaying monochrome.	Computer was turned on before the monitor was turned on. Video jumper incorrectly set.	Turn off the computer, turn on the monitor, then turn the computer back on. Set the jumper for color operation.  (See Main Logic Board Jumpers ).
Monitor fails to switch to high-resolution mode.	Appropriate high-resolution video drivers are not installed or incorrectly installed.	Correctly install all appropriate high-resolution video drivers.  Refer to an appropriate Video Adapter User's Guide and the documentation supplied with your monitor.
Monitor display not centered while loading Windows video drivers.	Monitor type incorrectly set.	Set the correct monitor type.  Refer to an appropriate Video Adapter User's Guide.


Computer Messages

This appendix lists the DECpc XL Series computer messages you might see or hear when you turn on power.  The computer messages are grouped as follows:

•	POST and Boot Messages

•	Beep Codes for Fatal Errors

•	Beep Codes for Nonfatal Errors

•	QAPlus Advanced Diagnostics

•	QAPlus Error Messages


POST and Boot Messages

The POST displays messages to alert you to errors in hardware, software, and firmware or to provide operating information about your computer.

Each time the POST displays a message on your screen, the computer's speaker beeps twice.  If an error occurs before the monitor is initialized, specific beep codes sound to alert you to a problem.  The table below lists a general grouping of system messages arranged by the POST countdown number.  In addition, each message is accompanied by text describing the message and in most cases, a recommended solution to the problem.

NOTE	Italics indicate variable parts of a message such as memory addresses, hexadecimal values, and so on.  These messages can differ at each occurrence.

POST Countdown Number	Message Number	Message	Solution
240	0007	No timer tick	Replace main logic board.
200	0001	Shutdown failure	Replace main logic board.
190	0009	Timer 2 failure	Replace main logic board.
180	0010	Keyboard stuck key Keyboard controller Keyboard clock line Keyboard data line Keyboard failure	Check the keyboard connection.  If the connection is secure, the keyboard or keyboard controller might have failed.  replace keyboard.
170	0041	Mouse failure	Check the mouse connection.  If the problem persists, replace the mouse.
160		640 KB base memory     0 KB extended memory
150	0017	Time-of-day clock stopped	Replace RTC.
100	0018	Invalid configuration information	Run the BIOS Setup utility.
090	0011	Diskette drive failure	Run the BIOS Setup utility.  Check all connections.  If the problem persists, replace the diskette drive.
080	0015	Hard disk controller failure	Run the BIOS Setup utility.  Check all connections.  If the problem persists, replace the controller.
080	0016	Hard disk 0 failure	Run the BIOS Setup utility.  Check all connections.  If the problem persists, replace the hard disk.
060	0021	xxxx0h optional ROM bad checksum = xx	Correct the address conflict. If the problem persists, replace the ROM chip.   .
050	0019	Time-of-day not set	Run BIOS Setup utility and set the time and date.
040	0020	Keyboard is locked	Unlock the keyboard.
020		Enable NMI
010		Enable cache
000		Boot


Beep Codes for Fatal Errors

If the POST finds an error and cannot display a message, the computer's speaker emits a series of beeps to indicate the error and places a value in I/O port 80h.

For example, a failure of bit 3 in the first 64 KB of RAM is indicated by a 2-1-4 beep code (a burst of two beeps, a single beep, and a burst of four beeps).

The table below lists the beep codes and the values the POST writes to I/O port 80h when it encounters a fatal error.  This table lists fatal errors that lock up the computer.  Nonfatal errors that do not lock up the computer are listed in a separate table.

See also:	Beep Codes for Nonfatal Errors

Beep Code	Error Message	Port 80h
1-1-3	CMOS write/read test or failure	02h
1-1-4	ROM checksum test or failure	03h
1-2-1	Interval timer test or failure	04h
1-2-2	DMA initialization or failure	05h
1-2-3	DMA page register write/read test or failure	06h
1-3-1	RAM refresh verification or failure	08h
1-3-3	1st 64 KB RAM chip or data line failure	0Ah
1-3-4	1st 64 KB RAM odd/even logic failure	0Bh
1-4-1	1st 64 KB RAM address line failure	0Ch
1-4-2	1st 64 KB RAM parity test or failure	0Dh
2-1-1	Bit 0 1st 64 KB RAM failure	10h
2-1-2	Bit 1 1st 64 KB RAM failure	11h
2-1-3	Bit 2 1st 64 KB RAM failure	12h
2-1-4	Bit 3 1st 64 KB RAM failure	13h
2-2-1	Bit 4 1st 64 KB RAM failure	14h
2-2-2	Bit 5 1st 64 KB RAM failure	15h
2-2-3	Bit 6 1st 64 KB RAM failure	16h
2-2-4	Bit 7 1st 64 KB RAM failure	17h
2-3-1	Bit 8 1st 64 KB RAM failure	18h
2-3-2	Bit 9 1st 64 KB RAM failure	19h
2-3-3	Bit A 1st 64 KB RAM failure	1Ah
2-3-4	Bit B 1st 64 KB RAM failure	1Bh
2-4-1	Bit C 1st 64 KB RAM failure	1Ch
2-4-2	Bit D 1st 64 KB RAM failure	1Dh
2-4-3	Bit E 1st 64 KB RAM failure	1Eh
2-4-4	Bit F 1st 64 KB RAM failure	1Fh
3-1-1	Slave DMA register test or failure	20h
3-1-2	Master DMA register test or failure	21h
3-1-3	Master interrupt mask register test or failure	22h
3-1-4	Slave interrupt mask register test or failure	23h
3-2-4	Keyboard/mouse controller test or failure	27h
4-2-1	Timer tick interrupt test or failure	34h
4-2-2	Shutdown test or failure	35h
4-2-3	Gate A20 failure	36h
4-2-4	Unexpected interrupt in protected mode	37h
4-3-1	RAM test or failure (above 0FFFFh)	38h
4-3-3	Interval timer 2 test or failure	3Ah
4-3-4	Time-of-day clock test or failure	3Bh
4-4-1	Serial port test or failure	3Ch
4-4-2	Parallel port test or failure	3Dh
4-4-3	Math coprocessor test or failure	3Eh


Beep Codes for Nonfatal Errors

If the POST finds an error and cannot display a message, the computer's speaker emits a series of beeps to indicate the error and places a value in I/O port 80h.

For example, a failure of bit 3 in the first 64 KB of RAM is indicated by a 2-1-4 beep code (a burst of two beeps, a single beep, and a burst of four beeps).

The table below lists the beep codes and the values the POST writes to I/O port 80h when it encounters a nonfatal error.  This table lists nonfatal errors that do not lock up the computer. Fatal errors that lock up the computer are listed in a separate table.

See also:	Beep Codes for Fatal Errors

Beep Code	Error Message	Port 80h
3-3-4	Screen memory test or failure	2Bh
3-4-1	Screen initialization or failure	2Ch
3-4-2	Screen retrace test or failure	2Dh


QAPlus Advanced Diagnostics

To:

•	Receive System Information, select SysInfo menu from the main menu.

•	Locate bad chips and run mouse and keyboard tests, select Interact menu.

•	Edit CMOS, select Setup menu.

•	Run tests on components, select Testing menu.

Default testing is No Pause on Errors/Single Pass/No Peripherals/No Error Logging/Test All Components.  To change default, select settings under the Testing menu before running tests.

See also:	QAPlus Error Messages


QAPlus Error Messages

Component	Messages	Solution
CPU	Arithmetic Function Failed	Reset CPU
	General Functions Failed	Replace CPU
	Exception Interrupt in Protected Mode
	Refresh Failure
	Logic Functions Failed
Hard disk	Butterfly Cylinder Access Test Failed	Low-level format hard disk
	Cylinder 0 Errors	Replace disk
	Random Cylinder Access Failed
	Linear Cylinder Access Failed
Hard drive/controller	Controller Diagnostic Test Failed	Run Setup
	Questionable Controller Card	Check connections
	Hard drives failed	Reset controller
		Replace controller
		Replace disk
Floppy diskette	Media Mismatch	Use known good diskette
	Drive Not Ready	Check size and density of diskette
	Unformatted Media	Close drive door
	Write Protected Media	Remove write protection
		Format diskette
Floppy drive	Floppy Drives Failed	Check connections
		Replace drive
Battery/clock	Clock Stopped	Run Setup
	Invalid Date	Replace battery/clock
	RTC Interrupt Failed
CMOS	CMOS Clock Test Failed	Change time from Setup menu in QAPLUS
Serial port	COM port failed	Check COM device
	Serial Chip Error	Check connections
	Serial Compare Error	Replace COM device
	Serial Timeout Error
Video adapter	Video Failed	Replace video adapter
	Error in Video Buffer


Technical Specifications

These topics provide information about the technical characteristics of the DECpc XL Series computers.

•	CPU Specifications

•	Thermal Considerations

•	External Computer Connectors

•	ISA Expansion Slots

•	PCI Local Bus Expansion Slots

•	Power Supply and Input Power

•	Nominal Current Requirements

•	Main Logic Board Jumpers


CPU Specifications

CPU specifications vary depending on the type of CPU module installed in your computer.  Refer to the supplied i486 or Pentium PCI Series CPU module booklet for further information.

•	Computer Performance Specifications

•	Computer Dimensions

•	Computer Environmental Specifications


Computer Performance Specifications

Attributes	Specification
Bus clock    ISA    PCI	7.5/8.33 MHz 30/33 MHz
Data I/O    ISA    PCI	8-bit and 16-bit 32-bit
Main logic board DRAM	8 MB standard up to 128 MB (i486 CPU module installed) up to 192 MB (Pentium CPU module installed)
ROM BIOS size	128 KB
Alkaline computer battery	3-year shelf life


Computer Dimensions

Dimension	Specification
Width	177.8 mm (7.0 in)
Length	431.8 mm (17.0 in)
Height (without pedestal)	431.8 mm (17.0 in)
Weight (without pedestal)	12.875 kg (28.359 lb)


Computer Environmental Specifications

Attributes	Specification
Operating temperature	10°C to 40°C (50°F to 104°F)
Storage temperature	−20°C to 65°C (−4°F to 149°F)
Operating humidity (noncondensing)	10% to 90% relative humidity,  maxium wet bulb 40°C  (104°F)
Storage humidity (noncondensing)	5% to 95% relative humidity,  maximum wet bulb 65°C  (149°F)
Altitude   Operating   Nonoperating	2,438 m (8,000 ft) maximum 4,876 m (16,000 ft) maximum
Shipping vibration	IAW Federal Standard 101, method 5019
Nonoperating shock	30 G, 25 ms halfsine


Thermal Considerations

•	If using three RZ26 disk drives (or compatible in relation to power consumption), the maximum operating temperature is 33°C/91°F

•	If using two RZ26 disk drives (or compatible in relation to power consumption), configure them is device bays 1 and 3


External Computer Connectors

These topics list the pin assignments for your computer's external connectors.

•	Parallel Printer Connector
25-pin D-submini female

•	Serial Port Connectors
9-pin D-submini male

•	Keyboard and Mouse Connectors
6-pin mini-DIN

•	SCSI-2 Interface Connector
50-pin female


Parallel Printer Connector

The parallel printer connector provides an interface to a printer or other parallel devices.  The table below lists pin assignments.  An asterisk (*) indicates an active low signal.

Parallel Printer Pinout

DB25 Pin	Signal	Function
1	STB-R*	Strobe
2	PRTD0	Printer data bit 0
3	PRTD1	Printer data bit 1
4	PRTD2	Printer data bit 2
5	PRTD3	Printer data bit 3
6	PRTD4	Printer data bit 4
7	PRTD5	Printer data bit 5
8	PRTD6	Printer data bit 6
9	PRTD7	Printer data bit 7
10	ACK*	Acknowledge
11	BUSY	Busy
12	PE	Paper end
13	SLCT	Select
14	AUTOFDXT*	Autofeed
15	ERR*	Error
16	INIT*	Initialize printer
17	SLCTIN*	Select input
18 to 25	GND	Ground


Serial Port Connectors

The serial port connectors consist of two 9-pin D-submini connectors. The two connectors are not interchangeable.  The table below lists the pins assignments.

The baud rates supported by the computer's serial ports are 300, 1200, 2400, 4800, 9600, 19 200, and 38 400.

9-Pin Serial Port Pinouts

DB9 Pin	Signal	Function
1	DCD	Data carrier detect
2	RXD	Receive data
3	TXD	Transmit data
4	DTR	Data terminal ready
5	GND	Ground
6	DSR	Data set ready
7	RTS	Request to send
8	CTS	Clear to send
9	RI	Ring indicator


Keyboard and Mouse Connectors

The keyboard and mouse connectors consist of two 6-pin mini-DIN connectors.  The table below lists the pin assignments.

Keyboard and Mouse Connector Pinouts

Pin	Signal
1	Data
2	Reserved
3	Ground
4	+5 V dc (fused)
5	Clock
6	No connection


SCSI-2 Connector

The SCSI-2 connector supports the ANSI Common Command Set and most SCSI-2 features.  The table below lists the pin assignments.  An asterisk (*) indicates an active low signal.

SCSI-2 Connector Pinouts

Pin	Signal
1	Ground
2	Data bit 0*
3	Ground
4	Data bit 1*
5	Ground
6	Data bit 2*
7	Ground
8	Data bit 3*
9	Ground
10	Data bit 4*
11	Ground
12	Data bit 5*
13	Ground
14	Data bit 6*
15	Ground
16	Data bit 7*
17	Ground
18	Parity bit*
19-22	Ground
23-24	Reserved
25	Open
26	Termpwr
27	Reserved
28	Reserved
29	Ground
30	Reserved
31	Ground
32	Attention*
33	Ground
34	Ground
35	Ground
36	Busy*
37	Ground
38	Acknowledge*
39	Ground
40	Reset*
41	Ground
42	Message*
43	Ground
44	Select*
45	Ground
46	Control/data*
47	Ground
48	Request*
49	Ground
50	Input*/output*


ISA Expansion Slots

The main logic board contains four ISA expansion slots.  The maximum available      +5 V dc current allowable to any expansion slot depend upon the following parameters:

•	Power supply capacity

•	The +5 V dc requirements of the main logic board and daughterboard

•	The +5 V dc requirements of the peripherals

•	The power demands of all other slots in use


PCI Local Bus Expansion Slots

The main logic board contains three PCI local bus expansion slots.  These slots support:

•	5 V dc only PCI expansion boards

•	5/3.3 V dc universal PCI expansion boards

•	One high-power PCI expansion slot (25 watts)

•	Two standard power PCI expansion slots (up to 15 watts)

•	PCI slots 2 and 3 support bus mastering

•	PCI slot 1 is a non-bus mastering slot only


Power Supply and Input Power Requirements

The power supply provides five dc voltages: +12 V dc, −12 V dc, +5 V dc, −5 V dc, and 3.3 V dc.  These voltages are used by the various components within the computer.  The table below lists the input power requirements.  Rated input current includes outlet current.

Computer Input Power Requirements

Rated  Voltage Range	Maximum Range	Rated Input Current	Operating Frequency Range
100 V ac - 120 V ac	88 V ac  - 132 V ac	8 A	47 Hz - 63 Hz
220 V ac - 240 V ac	176 V ac - 264 V ac	4 A	47 Hz - 63 Hz


Nominal Current Requirements

DECpc XL Series computers provide the following nominal current requirements:

•	+5 V  33 A

•	+12 V  7 A

•	-5 V  0.5 A

•	−12 V  0.5 A


Main Logic Board Jumpers

The table below lists the main logic board jumpers and factory-default settings.  The illustration shows the locations of the main logic board jumper pins.  Note that the square pin of each jumper block is pin 1.

CAUTION	Do not touch any electronic component unless you are safely grounded.  Wear a grounded wrist strap or touch an exposed metal part of the system box chassis.  A static discharge from your fingers can result in permanent damage to electronic components.

CAUTION	Do not use the password clear jumper (J32); use instead the clear CMOS jumper (J29).  Using the clear CMOS jumper then sets all your other CMOS settings back to the defaults.

See also:	CPU Module Jumper Settings (i486)
CPU Module Jumper Settings (Pentium)

Main Logic Board Jumper Settings  (1)=factory default setting

Feature	Description	Setting
Flash ROM upgrade	Enable(1) Disable	J35, jumpered(1) J35, open
Recovery mode	Normal(1) Recovery mode	J34, open(1) J34, jumpered
Display type	Mono(1) Color	J33, open(1) J33, jumpered
Password clear	Normal(1) Password clear (MFG test)	J32, open(1) J32, jumpered
Clear CMOS to default settings	Normal operation(1) Clear CMOS	J29, open(1) J29, jumpered


CPU Module Jumper Settings (i486)

Feature	Description	Setting
Cache size select  (default depends on the amount installed at the factory)	128 KB 256 KB	J8, pins 1 and 2 jumpered J9, pins 1 and 2 jumpered J10, pins 1 and 2 jumpered J8, pins 2 and 3 jumpered J9, pins 2 and 3 jumpered J10, pins 2 and 3 jumpered
CPU clock input (default depends on the CPU installed at the factory)	25 MHz 33 MHz	J12, pins 1 and 2 jumpered J12, pins 2 and 3 jumpered


CPU Module Jumper Settings (Pentium)

Feature	Description	Setting
CPU clock input (default depends on the CPU installed at the factory)	60 MHz 66 MHz	J5, pins 2 and 3 jumpered J5, pins 1 and 2 jumpered


Device Mapping

These Help topics list your computer's device mapping.

CPU Memory Address Map (Full Range)

CPU Memory Address Map (PC Compatibility Range)

CPU I/O Address Map

I/O Address Map

Computer Interrupt Levels

DMA Channel Assignment

PCI Configure Space Address Map


CPU Memory Address Map (Full Range)

Range	Description	Notes
0 - 512KB	main memory	PC compatibility range
512KB - 1024KB (1MB)	main memory	PC compatibility range ISA memory lower limit
1MB - 16-MB	main memory memory space gap	ISA memory upper limit PCI memory hole (4MB max size)
16MB - 128MB	main memory	i486 upper limit
128MB - 192MB	main memory	Pentium upper limit
192MB - 4GB	PCI memory


CPU Memory Address Map (PC Compatibility Range)

Address Range	Function	Size
0000 to 7FFFF	Main memory	512 KB
80000 to 9FFFF	Main/PCI/ISA memory	128 KB
A0000 to BFFFF	PCI/ISA video buffer memory	128 KB
C0000 to C7FFF	Video memory BIOS	32 KB
C8000 to DFFFF	PCI/ISA card BIOS and buffer memory	96 KB
E0000 to EBFFF	ISA/PCI adapter RAM after POST Used by BIOS Setup during POST	48 KB
EC000 to EFFFF	SCSI BIOS (if enabled)	16 KB
F0000 to FFFFF	Planar BIOS memory	64 KB


CPU I/O Address Map

Range (hexadecimal)	Function
0000 to 0CF7	PCI I/O space
0CF8	Configuration space enable register
0CF9	Turbo and reset control register
0CFA to BFFF	PCI I/O space
C000 to CFFF	PCI configuration space
D000 to FFFF	PCI I/O space


I/O Address Map

Range (hexadecimal)	Function
060 to 064	Keyboard/mouse controller
0F0 to 0FF	Math coprocesssor
1F0 to 1F7	IDE controller (if enabled)
278 to 27A	LPT2 (if enabled)
2F8 to 2FF	COM2 (if enabled)
378 to 37A	LPT1 (if enabled)
3BC to 3BE	LPT3 (if enabled)
3F0 to 3F7	Diskette controller (if enabled)
3F8 to 3FF	COM1 (if enabled)


Computer Interrupt Levels

Interrupt Number	Interrupt Source
IRQ1	Keyboard controller
IRQ3	COM2 (if enabled)
IRQ4	COM1 (if enabled)
IRQ6	Diskette drive (if enabled)
IRQ7	LPT1, LPT2, LPT3 (if enabled)
IRQ12	Mouse interrupt
IRQ13	Math coprocessor
IRQ14	Hard disk drive (if enabled)


DMA Channel Assignment

Channel	Controller	Function
0	1	Refresh
1	1	Not used
2	1	Diskette controller (if enabled)
3	1	Not used
4	2	Cascade DMA
5	2	Not used
6	2	IDE (if enabled)
7	2	Not used


PCI Configure Space Address Map

Range (hexadecimal)	Function
C0xx	CPU bridge
C1xx	Onboard PCI SCSI
C2xx	ISA bridge
C6xx	PCI slot 1
C7xx	PCI slot 2
C8xx	PCI slot 3


928/PCI Video Adapter

This group of Help topics describes how to:

•	Configure your computer for high performance video resolution

•	Install the device drivers supplied on the two S3 86C928PCI video diskettes

The following specific topics are available:

Video Adapter Kit Contents

System Requirements

Conventions

Features

Installation Procedures - Overview

Setting the Monitor Type (MS-DOS)

Setting the Video Adapter Type

Installing Video Support - Overview

Installing Video Drivers (Microsoft Windows)

Installing Video Drivers (MS-DOS or CAD)

SMODE for Non-Standard VGA Display

Additional Documentation


Video Adapter Kit Contents

The 928 PCI Bus Video Adapter kit contains the following:

•	One video adapter

•	One DECpc 928 PCI Bus Video Adapter User Guide

•	One PCI Bus S3 86C928PCI VGA Utilities and DOS Video Drivers diskette, which includes:

SMTR.EXE

SMODE.EXE

MS-DOS and CAD video drivers

README files

•	One S3 86C928PCI Windows Drivers diskette


Additional Documentation (Video Adapters)

Use the DECpc 928 PCI Bus Video Adapter User's Guide (or other printed documentation provided with your video adapter) as a supplement to the information provided in this Help file.  Also, refer to the documentation supplied with the monitor and read any README files on your S3 86C928PCI VGA Utilities and Windows Drivers diskettes.


Conventions (Video Adapter Topics)

The video adapter help topics use the following conventions:

Convention	Description
UPPERCASE	Commands are shown in UPPERCASE to separate them from the text.
[Enter]	Square brackets surrounding text represent a key on the keyboard.
<hex mode>	Monospaced text indicates file names, screen names, or screen text.


Features (Video Adapter)

The video adapter performance features are:

•	PCI Bus Video Interface — This non-bus mastering interface provides a no-wait-state, read/write cycle operating up to 33 MHz to improve video performance.

A linear addressing scheme allows memory to be mapped into the CPU's upper memory address space. This results in software flexibility and extendibility.

•	Video DAC Support — The video adapter uses a 24-bit true color VGA compatible palette, which can display up to 16.8 million colors.


System Requirements (Video Adapter)

The video adapter is designed for use in a 32-bit PCI bus expansion slot such as provided by DECpc XL computers.

The 928 PCI Bus Video Adapters are set at the factory for 640 × 480 resolution.

Your video adapter's capabilities must match your monitor's resolution. If your monitor supports a higher resolution, you can reconfigure to match the monitor's high resolution specification.

•	Refer to your monitor documentation and the rest of this Help file for more information about configuring your computer.

The table below lists the monitor resolutions, refresh rates, and video memory requirements supported by the video adapter.

CAUTION	Do not connect a low-resolution monitor to a computer configured with high-resolution video drivers.  High-resolution video drivers can damage a 640 × 480 monitor.

Resolution	Refresh Rate (I)  Interlaced	Colors
640 × 480	60 Hz	16
640 × 480	60 Hz, 72 Hz	256
640 × 480	60 Hz	32 768
640 × 480	60 Hz	65 536
640 × 480	60 Hz	16.7 M
800 × 600	56 Hz, 60 Hz, 72 Hz	16
800 × 600	56 Hz, 60 Hz, 72 Hz	256
800 × 600	60 Hz	65 536
1024 × 768	43 Hz (I), 60 Hz, 70 Hz	16
1024 × 768	43 Hz (I), 60 Hz, 70 Hz	256
1280 × 1024	43 Hz (I), 60 Hz	16


Video Adapter Installation - Overview

If your computer was delivered with factory installed software, you only need to change its configuration if you have a monitor that supports a higher resolution and you choose to increase the resolution of your monitor.

CAUTION	Do not connect a low resolution monitor to a computer that is configured with high-resolution video drivers. High resolution video drivers can damage a 640 × 480 video monitor.

The following steps provide an overview of the installation process.

If your video adapter is...	And you want to ...	Then do the following:
Installed in the your computer	Increase resolution with a high resolution monitor	1. Find the resolution and refresh rate, and/or vertical synchronization specifications. • Refer to your monitor's documentation. • Refer to Installing Video Drivers (Microsoft Windows)  or Installing Video Drivers (MS-DOS or CAD) for more specific installation instructions.
Not installed in your computer	Install the video adapter	1. Remove the computer's side panel and locate the PCI bus slots.  Also, determine the PCI slot that best fits your specific needs • Refer to your computer's user guide. 2. Refer to Chapter 2 of your DECpc 928 PCI Bus Video Adapter User's Guide for hardware installation instructions. 3. Setup and install the software drivers. • Refer to Installing Video Drivers (Microsoft Windows)  or Installing Video Drivers (MS-DOS or CAD) for more specific installation instructions.


Installing Video Support - Overview

To configure and install the software for the video support of your computer or to change the resolution on your monitor you need to:

1.	Set your video adapter type using the BIOS Setup utility.

2.	Set your monitor type using SMTR.EXE.

3.	Install the appropriate video drivers.

NOTE	If you have an application that does not support standard VGA modes, you must use the SMODE utility to display or emulate the appropriate non-standard VGA mode.  Refer to "SMODE for Non-Standard VGA Display," in this chapter.


Setting the Video Adapter Type

After installing the hardware, you need to access the BIOS Setup utility to set the correct video adapter type.  To access the BIOS Setup utility:

1.	Turn on or reboot your computer and allow POST to complete.

2.	Make a note of any configuration errors listed (if any) and then press F1 to display the first of three setup screens.

3.	Highlight the video adapter option and then select the correct video adapter type.

•	Refer to the documentation supplied with your computer for instructions on running the BIOS Setup utility.

4.	Exit the BIOS Setup utility following the instructions on the monitor screen.


Setting the Monitor Type (MS-DOS)

Your PCI bus video adapter's monitor type selection must match your monitor's available resolution and refresh rates.  These monitor resolution and refresh rates are listed in your monitor's support documentation and in the SMTR.EXE utility on the PCI Bus S3 86C928 VGA Utilities and DOS Video Drivers diskette.  To select the correct monitor type, follow the steps listed below.

CAUTION	Do not select a monitor type setting that exceeds your monitor's resolution, refresh rate (vertical synchronization), and interlace or non-interlace specifications.  Refer to you monitor's documentation for performance specifications.

1.	Turn on or reboot your computer and allow POST to complete.

2.	Insert the PCI Bus S3 86C928 VGA Utilities and DOS Video Drivers diskette into drive A.

3.	Type A: then press [Enter].

4.	Type CD\UTILS and press [Enter].

5.	Type SMTR and press [Enter].

6.	Select the correct monitor type following the instructions on your monitor screen.

Example
If you want to run your monitor at a resolution of 1024×768, select 1024x768@72Hz/NI.

7.	Exit the SMTR.EXE utility following the instructions on your monitor screen.

8.	Remove the PCI Bus S3 86C928 VGA Utilities and DOS Video Drivers diskette.

If you want to access SMTR from your computer's hard disk drive, create a directory and then copy the SMTR.exe file into it.

After you configure your computer, you are now ready to install the appropriate video drivers for either:

•	Microsoft Windows applications

•	MS-DOS or CAD applications


Installing Video Drivers (Microsoft Windows)

Install the Microsoft Windows video drivers as follows:

1.	Type CD WINDOWS at the C:\> prompt, then press [Enter]

The following prompt appears:  C:\WINDOWS>.

2.	Type SETUP and press [Enter].

Your computer displays the SETUP screen.

3.	Select the Display option and press [Enter].

4.	Toggle through the Display option to select
Other (Requires disk provided by hardware manufacturer).

5.	Place the PCI Bus S3 86C928 Windows Drivers diskette in drive A, then press [Enter].

A list of S3 video drivers appears in a box at the bottom the screen.

6.	Select the desired video resolution then press [Enter].

NOTE	The resolution and refresh rate must be the same as the selection made using the SMTR.EXE utility.

Example
If you select 1024x768@72Hz/NI using the SMTR.EXE utility, an appropriate selection is:
S3 86C928 V1.1 1024x768 256 Colors Large Fonts.

The Video Setup screen appears again with the S3 driver.

Press [Enter] to accept the configuration.

7.	The MS-DOS prompt appears when Setup completes.

Type WIN and press [Enter] to start Microsoft Windows.


Installing Video Drivers (MS-DOS or CAD)

Installing MS-DOS or CAD video drivers differ with each software application.  Specific instructions are located in the README.DOS file and in the appropriate MS-DOS or CAD application directories and files.  Follow the procedures on the PCI Bus S3 86C928 VGA Utilities and DOS Video Drivers diskette.

Note that you might not be able to install MS-DOS or CAD video drivers from within Windows.


SMODE for Non-Standard VGA Display

The SMODE utility allows your video adapter's video circuitry to emulate and display non-standard VGA modes.  With SMODE, you can run software applications written for the following non-VGA modes:

•	Monochrome adapter (MDA)

•	Color graphics adapter (CGA)

•	Expanded graphics adapter (EGA)

•	Hercules monochrome graphics adapter (HGC)

The following procedure describes how to access SMODE.

1.	Insert the PCI Bus S3 86C928 VGA Utilities and DOS Video Drivers diskette into drive A.

2.	Type A: then press [Enter].

3.	Type CD\UTILS and press [Enter].  Refer to the table below for instructions on using SMODE.

4.	Remove the PCI Bus S3 86C928 VGA Utilities and DOS Video Drivers diskette.

If you want to access SMODE from your computer's hard disk drive, create a directory and then copy the SMODE.exe file into it.

If you want to...	Type SMODE  followed by...	Example
Display a non-standard VGA mode	<hex mode #> VGA	SMODE 55 VGA
VGA modes and corresponding hexadecimal numbers are listed in the Release Notes supplied with your video adapter.

Emulate a non-VGA mode	Either EGA, CGA, MDA, or Hercules	SMODE MDA
SMODE MDA allows your main logic board's video circuitry to emulate a monochrome adapter.