HP Deskpro EX Use and care manual

Technical Reference Guide
For the
Compaq Deskpro EX/EXS Series of Personal Computers
Covering Models Featuring
Intel Celeron and Pentium III Processors
And the
Intel 815 Chipset

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the edge of the binder.
Deskpro EX Series Personal Computers
Featuring Intel Celeron and Pentium III Processors
and the Intel 815 Chipset TRG

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Technical Reference Guide
Compaq Deskpro EX Series of Personal Computers
First Edition - August 2000
i
NOTICE
The information in this document is subject to change without notice.
COMPAQ COMPUTER CORPORATION SHALL NOT BE LIABLE FOR TECHNICAL OR
EDITORIAL ERRORS OR OMISSIONS HEREIN; NOR FOR INCIDENTAL OR
CONSEQUENTIAL DAMAGES RESULTING FROM THE FURNISHING, PERFORMANCE,
OR USE OF THIS MATERIAL. IT IS THE RESPONSIBILITY OF MANUFACTURERS TO
ENSURE THAT DEVICES DESIGNED TO BE USED WITH COMPAQ PRODUCTS
COMPLY WITH FCC CLASS B EMISSIONS REQUIREMENTS.
This guide contains information protected by copyright. Except for use in connection with the
described Compaq product, no part of this document may be photocopied or reproduced in any
form without prior written consent from Compaq Computer Corporation.
2000 Compaq Computer Corporation
All rights reserved. Published in the USA
Compaq, Deskpro, LTE, Contura, Presario, ProLinea
Registered U.S. Patent and Trademark Office
Product names mentioned in this document may be trademarks and/or registered trademarks of other companies.
“Celeron,” “Pentium” and “MMX” are registered trademarks of Intel Corporation.
“Microsoft,” “MS-DOS,” “Windows,” and “Windows NT” are registered trademarks of Microsoft Corporation.
For more information regarding specifications and Compaq-specific parts please contact Compaq
Computer Corporation.
Technical Reference Guide
for
Compaq Deskpro EX Series Personal Computers
First Edition - August 2000
Document Number 137H-0800A-WWEN

Technical Reference Guide
Compaq Deskpro EX Series of Personal Computers
First Edition –- August 2000
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Technical Reference Guide
Compaq Deskpro EX Series of Personal Computers
First Edition - August 2000
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ii
TABLE OF CONTENTS
CHAPTER 1 INTRODUCTION..................................................................................................................
1.1 ABOUT THIS GUIDE ................................................................................................................1-1
1.1.1 USING THIS GUIDE..........................................................................................................1-1
1.1.2 ADDITIONAL INFORMATION SOURCES .....................................................................1-1
1.2 MODEL NUMBERING CONVENTION ...................................................................................1-1
1.3 NOTATIONAL CONVENTIONS ..............................................................................................1-2
1.3.1 VALUES..............................................................................................................................1-2
1.3.2 RANGES..............................................................................................................................1-2
1.3.3 SIGNAL LABELS...............................................................................................................1-2
1.3.4 REGISTER NOTATION AND USAGE.............................................................................1-2
1.3.5 BIT NOTATION .................................................................................................................1-2
1.4 COMMON ACRONYMS AND ABBREVIATIONS .................................................................1-3
CHAPTER 2 SYSTEM OVERVIEW..........................................................................................................
2.1 INTRODUCTION .......................................................................................................................2-1
2.2 FEATURES AND OPTIONS......................................................................................................2-2
2.2.1 STANDARD FEATURES...................................................................................................2-2
2.2.2 OPTIONS.............................................................................................................................2-3
2.3 MECHANICAL DESIGN............................................................................................................2-4
2.3.1 CABINET LAYOUTS.........................................................................................................2-5
2.3.2 CHASSIS LAYOUTS..........................................................................................................2-7
2.3.3 BOARD LAYOUT ..............................................................................................................2-9
2.4 SYSTEM ARCHITECTURE.....................................................................................................2-10
2.4.1 PROCESSORS...................................................................................................................2-12
2.4.2 CHIPSET ...........................................................................................................................2-14
2.4.3 SUPPORT COMPONENTS..............................................................................................2-14
2.4.4 SYSTEM MEMORY.........................................................................................................2-15
2.4.5 MASS STORAGE .............................................................................................................2-15
2.4.6 SERIAL AND PARALLEL INTERFACES......................................................................2-15
2.4.7 UNIVERSAL SERIAL BUS INTERFACE.......................................................................2-15
2.4.8 GRAPHICS SUBSYSTEM ...............................................................................................2-16
2.4.9 AUDIO SUBSYSTEM ......................................................................................................2-17
2.5 SPECIFICATIONS....................................................................................................................2-17
CHAPTER 3 PROCESSOR/MEMORY SUBSYSTEM.............................................................................
3.1 INTRODUCTION .......................................................................................................................3-1
3.2 PROCESSOR...............................................................................................................................3-2
3.2.1 CELERON PROCESSOR....................................................................................................3-2
3.2.2 PENTIUM III PROCESSOR...............................................................................................3-3
3.2.3 PROCESSOR UPGRADING ..............................................................................................3-4
3.3 MEMORY SUBSYSTEM...........................................................................................................3-5
3.4 SUBSYSTEM CONFIGURATION ............................................................................................3-8

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First Edition –- August 2000
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CHAPTER 4 SYSTEM SUPPORT..............................................................................................................
4.1 INTRODUCTION .......................................................................................................................4-1
4.2 PCI BUS OVERVIEW ................................................................................................................4-2
4.2.1 PCI BUS TRANSACTIONS ...............................................................................................4-3
4.2.2 PCI BUS MASTER ARBITRATION..................................................................................4-6
4.2.3 OPTION ROM MAPPING..................................................................................................4-7
4.2.4 PCI INTERRUPTS..............................................................................................................4-7
4.2.5 PCI POWER MANAGEMENT SUPPORT ........................................................................4-7
4.2.6 PCI SUB-BUSSES...............................................................................................................4-7
4.2.7 PCI CONFIGURATION......................................................................................................4-8
4.2.8 PCI CONNECTOR..............................................................................................................4-9
4.3 AGP BUS OVERVIEW.............................................................................................................4-10
4.3.1 BUS TRANSACTIONS.....................................................................................................4-10
4.3.2 AGP CONFIGURATION..................................................................................................4-13
4.3.3 AGP CONNECTOR ..........................................................................................................4-14
4.4 SYSTEM RESOURCES............................................................................................................4-15
4.4.1 INTERRUPTS ...................................................................................................................4-15
4.4.2 DIRECT MEMORY ACCESS ..........................................................................................4-19
4.5 SYSTEM CLOCK DISTRIBUTION ........................................................................................4-22
4.6 REAL-TIME CLOCK AND CONFIGURATION MEMORY..................................................4-23
4.6.1 CLEARING CMOS ...........................................................................................................4-23
4.6.2 CMOS ARCHIVE AND RESTORE..................................................................................4-24
4.6.3 STANDARD CMOS LOCATIONS ..................................................................................4-24
4.7 SYSTEM MANAGEMENT......................................................................................................4-33
4.7.1 SECURITY FUNCTIONS.................................................................................................4-33
4.7.2 POWER MANAGEMENT................................................................................................4-35
4.7.3 SYSTEM STATUS............................................................................................................4-35
4.7.4 TEMPERATURE SENSING.............................................................................................4-36
4.8 SYSTEM COOLING.................................................................................................................4-37
4.9 REGISTER MAP AND MISCELLANEOUS FUNCTIONS....................................................4-38
4.9.1 SYSTEM I/O MAP............................................................................................................4-38
4.9.2 82801 ICH GENERAL PURPOSE FUNCTIONS.............................................................4-39
4.9.3 LPC47B357 I/O CONTROLLER FUNCTIONS...............................................................4-40
CHAPTER 5 INPUT/OUTPUT INTERFACES..........................................................................................
5.1 INTRODUCTION .......................................................................................................................5-1
5.2 ENHANCED IDE INTERFACE.................................................................................................5-1
5.2.1 IDE PROGRAMMING........................................................................................................5-1
5.2.2 IDE CONNECTOR..............................................................................................................5-3
5.3 DISKETTE DRIVE INTERFACE ..............................................................................................5-4
5.3.1 DISKETTE DRIVE PROGRAMMING..............................................................................5-5
5.3.2 DISKETTE DRIVE CONNECTOR....................................................................................5-7
5.4 SERIAL INTERFACE.................................................................................................................5-8
5.4.1 RS-232 INTERFACE...........................................................................................................5-8
5.4.2 SERIAL INTERFACE PROGRAMMING..........................................................................5-9

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Compaq Deskpro EX Series of Personal Computers
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5.5 PARALLEL INTERFACE.........................................................................................................5-10
5.5.1 STANDARD PARALLEL PORT MODE.........................................................................5-10
5.5.2 ENHANCED PARALLEL PORT MODE.........................................................................5-11
5.5.3 EXTENDED CAPABILITIES PORT MODE...................................................................5-11
5.5.4 PARALLEL INTERFACE PROGRAMMING .................................................................5-11
5.5.5 PARALLEL INTERFACE CONNECTOR .......................................................................5-13
5.6 KEYBOARD/POINTING DEVICE INTERFACE...................................................................5-14
5.6.1 KEYBOARD INTERFACE OPERATION.......................................................................5-14
5.6.2 POINTING DEVICE INTERFACE OPERATION...........................................................5-16
5.6.3 KEYBOARD/POINTING DEVICE INTERFACE PROGRAMMING...........................5-16
5.6.4 KEYBOARD/POINTING DEVICE INTERFACE CONNECTOR..................................5-19
5.7 UNIVERSAL SERIAL BUS INTERFACE...............................................................................5-20
5.7.1 USB DATA FORMATS....................................................................................................5-20
5.7.2 USB PROGRAMMING.....................................................................................................5-22
5.7.3 USB CONNECTOR ..........................................................................................................5-23
5.7.4 USB CABLE DATA..........................................................................................................5-23
5.8 AUDIO SUBSYSTEM..............................................................................................................5-24
5.8.1 FUNCTIONAL ANALYSIS..............................................................................................5-24
5.8.2 AC97 AUDIO CONTROLLER.........................................................................................5-26
5.8.3 AC97 LINK BUS...............................................................................................................5-26
5.8.4 AUDIO CODEC ................................................................................................................5-27
5.8.5 AUDIO PROGRAMMING................................................................................................5-28
5.8.6 AUDIO SPECIFICATIONS..............................................................................................5-29
5.9 NETWORK SUPPORT.............................................................................................................5-30
5.9.1 PCI VER. 2.2 SUPPORT...................................................................................................5-30
5.9.2 ALERT-ON-LAN SUPPORT............................................................................................5-30
5.9.3 REMOTE SYSTEM ALERT SUPPORT ..........................................................................5-32
CHAPTER 6 EMBEDDED GRAPHICS SUBSYSTEM............................................................................
6.1 INTRODUCTION .......................................................................................................................6-1
6.1.1 FEATURE SUMMARY......................................................................................................6-1
6.2 815-BASED GRAPHICS FUNCTIONAL DESCRIPTION........................................................6-2
6.2.1 DISPLAY MODES..............................................................................................................6-4
6.3 815-BASED GRAPHICS PROGRAMMING .............................................................................6-5
6.4 MONITOR POWER MANAGEMENT CONTROL...................................................................6-5
6.5 MONITOR CONNECTOR..........................................................................................................6-6
6.6 UPGRADING 815-BASED GRAPHICS....................................................................................6-6
CHAPTER 7 POWER SUPPLY AND DISTRIBUTION...........................................................................
7.1 INTRODUCTION .......................................................................................................................7-1
7.1 POWER SUPPLY ASSEMBLY/CONTROL..............................................................................7-1
7.1.1 POWER SUPPLY ASSEMBLY..........................................................................................7-2
7.1.2 POWER CONTROL............................................................................................................7-3
7.2 POWER DISTRIBUTION...........................................................................................................7-5
7.2.1 3.3/5/12 VDC DISTRIBUTION..........................................................................................7-5
7.2.2 LOW VOLTAGE DISTRIBUTION....................................................................................7-7
7.3 SIGNAL DISTRIBUTION..........................................................................................................7-8

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First Edition –- August 2000
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CHAPTER 8 BIOS ROM................................................................................................................................
8.1 INTRODUCTION .......................................................................................................................8-1
8.2 ROM FLASHING........................................................................................................................8-2
8.2.1 UPGRADING......................................................................................................................8-2
8.2.2 CHANGEABLE SPLASH SCREEN...................................................................................8-3
8.3 BOOT FUNCTIONS ...................................................................................................................8-4
8.3.1 BOOT DEVICE ORDER.....................................................................................................8-4
8.3.2 NETWORK BOOT (F12) SUPPORT .................................................................................8-4
8.3.3 MEMORY DETECTION AND CONFIGURATION.........................................................8-5
8.3.4 BOOT ERROR CODES ......................................................................................................8-5
8.4 SETUP UTILITY ........................................................................................................................8-6
8.5 CLIENT MANAGEMENT FUNCTIONS ................................................................................8-12
8.5.1 SYSTEM ID AND ROM TYPE........................................................................................8-14
8.5.2 EDID RETRIEVE..............................................................................................................8-14
8.5.3 TEMPERATURE STATUS ..............................................................................................8-15
8.5.4 DRIVE FAULT PREDICTION.........................................................................................8-15
8.6 PNP SUPPORT..........................................................................................................................8-15
8.6.1 SMBIOS.............................................................................................................................8-16
8.7 POWER MANAGEMENT FUNCTIONS.................................................................................8-17
8.7.1 INDEPENDENT PM SUPPORT.......................................................................................8-17
8.7.2 ACPI SUPPORT................................................................................................................8-19
8.7.3 APM 1.2 SUPPORT ..........................................................................................................8-19
8.8 USB LEGACY SUPPORT........................................................................................................8-23
A. APPENDIX A ERROR MESSAGES AND CODES...........................................................................
A.1 INTRODUCTION ......................................................................................................................A-1
A.2 BEEP/KEYBOARD LED CODES.............................................................................................A-1
A.3 POWER-ON SELF TEST (POST) MESSAGES........................................................................A-2
A.4 SYSTEM ERROR MESSAGES (1XX-XX).................................................................................A-3
A.5 MEMORY ERROR MESSAGES (2XX-XX)...............................................................................A-4
A.6 KEYBOARD ERROR MESSAGES (30X-XX)...........................................................................A-4
A.7 PRINTER ERROR MESSAGES (4XX-XX)................................................................................A-5
A.8 VIDEO (GRAPHICS) ERROR MESSAGES (5XX-XX).............................................................A-5
A.9 DISKETTE DRIVE ERROR MESSAGES (6XX-XX) ................................................................A-6
A.10 SERIAL INTERFACE ERROR MESSAGES (11XX-XX)..........................................................A-6
A.11 MODEM COMMUNICATIONS ERROR MESSAGES (12XX-XX)..........................................A-7
A.12 SYSTEM STATUS ERROR MESSAGES (16XX-XX)...............................................................A-8
A.13 HARD DRIVE ERROR MESSAGES (17XX-XX) ......................................................................A-8
A.14 HARD DRIVE ERROR MESSAGES (19XX-XX) ......................................................................A-9
A.15 VIDEO (GRAPHICS) ERROR MESSAGES (24XX-XX)...........................................................A-9
A.16 AUDIO ERROR MESSAGES (3206-XX) ................................................................................A-10
A.17 DVD/CD-ROM ERROR MESSAGES (33XX-XX)...................................................................A-10
A.18 NETWORK INTERFACE ERROR MESSAGES (60XX-XX)..................................................A-10
A.19 SCSI INTERFACE ERROR MESSAGES (65XX-XX, 66XX-XX, 67XX-XX).............................A-11
A.20 POINTING DEVICE INTERFACE ERROR MESSAGES (8601-XX)....................................A-11

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First Edition - August 2000
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APPENDIX B ASCII CHARACTER SET..................................................................................................
B.1 INTRODUCTION ......................................................................................................................B-1
APPENDIX C KEYBOARD.........................................................................................................................
C.1 INTRODUCTION ...................................................................................................................... C-1
C.2 KEYSTROKE PROCESSING....................................................................................................C-2
C.2.1 PS/2-TYPE KEYBOARD TRANSMISSIONS.................................................................. C-3
C.2.2 USB-TYPE KEYBOARD TRANSMISSIONS..................................................................C-4
C.2.3 KEYBOARD LAYOUTS................................................................................................... C-5
C.2.4 KEYS..................................................................................................................................C-8
C.2.5 KEYBOARD COMMANDS............................................................................................C-11
C.2.6 SCAN CODES..................................................................................................................C-11
C.3 CONNECTORS........................................................................................................................C-16
APPENDIX D COMPAQ/NVIDIA VANTA LT AGP GRAPHICS CARD .......................................D-1
D.1 INTRODUCTION ......................................................................................................................D-1
D.2 FUNCTIONAL DESCRIPTION ................................................................................................D-2
D.3 DISPLAY MODES.....................................................................................................................D-3
D.4 SOFTWARE SUPPORT INFORMATION................................................................................D-4
D.5 POWER MANAGEMENT AND CONSUMPTION..................................................................D-4
D.6 CONNECTORS..........................................................................................................................D-5
D.6.1 MONITOR CONNECTOR.................................................................................................D-5
APPENDIX E COMPAQ/NVIDIA M64 GRAPHICS CARD ...................................................................
E.1 INTRODUCTION ...................................................................................................................... E-1
E.2 FUNCTIONAL DESCRIPTION ................................................................................................ E-2
E.3 DISPLAY MODES..................................................................................................................... E-3
E.4 SOFTWARE SUPPORT INFORMATION................................................................................ E-4
E.5 MONITOR CONTROL..............................................................................................................E-4
E.6 CONNECTORS.......................................................................................................................... E-5
E.6.2 MONITOR CONNECTOR................................................................................................. E-5
E.6.3 VIDEO INTERFACE CONNECTOR................................................................................ E-6

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First Edition –- August 2000
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LIST OF FIGURES
FIGURE 2–1. COMPAQ DESKPRO EX SERIES PERSONAL COMPUTERS WITH MONITORS..............................2-1
FIGURE 2–2. COMPAQ DESKPRO EX SERIES, FRONT VIEWS.......................................................................2-5
FIGURE 2–3. COMPAQ DESKPRO EX SERIES, REAR VIEWS ........................................................................2-6
FIGURE 2–4. COMPAQ DESKPRO EX DESKTOP (DT) CHASSIS LAYOUT, TOP VIEW ...................................2-7
FIGURE 2–5. COMPAQ DESKPRO EX MINITOWER (MT) CHASSIS LAYOUT, SIDE VIEW..............................2-8
FIGURE 2–6. SYSTEM BOARD LAYOUT......................................................................................................2-9
FIGURE 2–7. COMPAQ DESKPRO EX ARCHITECTURE, BLOCK DIAGRAM ...................................................2-11
FIGURE 2–8. PROCESSOR ASSEMBLY AND MOUNTING.............................................................................2-12
FIGURE 3–1. PROCESSOR/MEMORY SUBSYSTEM ARCHITECTURE ..............................................................3-1
FIGURE 3–2. CELERON PROCESSOR INTERNAL ARCHITECTURE..................................................................3-2
FIGURE 3–3. PENTIUM III PROCESSOR INTERNAL ARCHITECTURE .............................................................3-3
FIGURE 3–4. SYSTEM MEMORY MAP .........................................................................................................3-7
FIGURE 4-1. PCI BUS DEVICES AND FUNCTIONS .........................................................................................4-2
FIGURE 4-2. CONFIGURATION CYCLE .........................................................................................................4-4
FIGURE 4-3. PCI CONFIGURATION SPACE MAPPING ...................................................................................4-5
FIGURE 4-4. PCI BUS CONNECTOR (32-BIT TYPE).....................................................................................4-9
FIGURE 4-5. AGP 1X DATA TRANSFER (PEAK TRANSFER RATE: 266 MB/S) ..........................................4-11
FIGURE 4-6. AGP 2X DATA TRANSFER (PEAK TRANSFER RATE: 532 MB/S) ..........................................4-12
FIGURE 4-7. AGP 4X DATA TRANSFER (PEAK TRANSFER RATE: 1064 MB/S) ........................................4-12
FIGURE 4-8. UNIVERSAL AGP BUS CONNECTOR......................................................................................4-14
FIGURE 4-9. MASKABLE INTERRUPT PROCESSING, BLOCK DIAGRAM.......................................................4-15
FIGURE 4-10. CONFIGURATION MEMORY MAP.........................................................................................4-23
FIGURE 4-11. FAN CONTROL BLOCK DIAGRAM .........................................................................................4-37
FIGURE 5-1. 40-PIN PRIMARY IDE CONNECTOR (ON SYSTEM BOARD)........................................................5-3
FIGURE 5-2. 34-PIN DISKETTE DRIVE CONNECTOR.....................................................................................5-7
FIGURE 5-3. SERIAL INTERFACE CONNECTOR (MALE DB-9 AS VIEWED FROM REAR OF CHASSIS)...............5-8
FIGURE 5-4. PARALLEL INTERFACE CONNECTOR (FEMALE DB-25 AS VIEWED FROM REAR OF CHASSIS)..5-13
FIGURE 5-5. 8042-TO-KEYBOARD TRANSMISSION OF CODE EDH, TIMING DIAGRAM...............................5-14
FIGURE 5-6. KEYBOARD OR POINTING DEVICE INTERFACE CONNECTOR ..................................................5-19
FIGURE 5-7. USB I/F, BLOCK DIAGRAM ...................................................................................................5-20
FIGURE 5-8. USB PACKET FORMATS ........................................................................................................5-21
FIGURE 5-9. UNIVERSAL SERIAL BUS CONNECTOR ...................................................................................5-23
FIGURE 5-10. AUDIO SUBSYSTEM FUNCTIONAL BLOCK DIAGRAM............................................................5-25
FIGURE 5-11. AC’97 LINK BUS PROTOCOL...............................................................................................5-26
FIGURE 5-12. AD1885 AUDIO CODEC FUNCTIONAL BLOCK DIAGRAM.....................................................5-27
FIGURE 5-13. AOL IMPLEMENTATION (GENERIC REPRESENTATION)........................................................5-31
FIGURE 5-14. REMOTE SENSE ALERT IMPLEMENTATION (GENERIC REPRESENTATION)............................5-32
FIGURE 5-15. RSA LOGIC, BLOCK DIAGRAM............................................................................................5-32
FIGURE 6-1. 815E-BASED GRAPHICS, BLOCK DIAGRAM.............................................................................6-2
FIGURE 6-2. 82815 GMCH INTEGRATED GRAPHICS SUBSYSTEM..............................................................6-3
FIGURE 7–1. POWER DISTRIBUTION AND CONTROL, BLOCK DIAGRAM .......................................................7-1
FIGURE 7–2. DESKPRO EX DT POWER CABLE DIAGRAM...........................................................................7-5
FIGURE 7–3. DESKPRO EX MT POWER CABLE DIAGRAM ..........................................................................7-6
FIGURE 7–4. LOW VOLTAGE SUPPLY AND DISTRIBUTION DIAGRAM ...........................................................7-7
FIGURE 7–5. SIGNAL DISTRIBUTION DIAGRAM (TYPICAL CONFIGURATION)...............................................7-8
FIGURE 7–6. HEADER PINOUTS...................................................................................................................7-9

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First Edition - August 2000
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FIGURE B–1. ASCII CHARACTER SET ....................................................................................................... B-1
FIGURE C–1. KEYSTROKE PROCESSING ELEMENTS, BLOCK DIAGRAM...................................................... C-2
FIGURE C–2. PS/2 KEYBOARD-TO-SYSTEM TRANSMISSION, TIMING DIAGRAM ....................................... C-3
FIGURE C–3. U.S. ENGLISH (101-KEY) KEYBOARD KEY POSITIONS......................................................... C-5
FIGURE C–4. NATIONAL (102-KEY) KEYBOARD KEY POSITIONS .............................................................. C-5
FIGURE C–5. U.S. ENGLISH WINDOWS (101W-KEY) KEYBOARD KEY POSITIONS .................................... C-6
FIGURE C–6. NATIONAL WINDOWS (102W-KEY) KEYBOARD KEY POSITIONS ......................................... C-6
FIGURE C–7. 7-BUTTON EASY ACCESS KEYBOARD LAYOUT .................................................................... C-7
FIGURE C–8. 8-BUTTON EASY ACCESS KEYBOARD LAYOUT .................................................................... C-7
FIGURE C–9. PS/2 KEYBOARD CABLE CONNECTOR (MALE)................................................................... C-16
FIGURE C–10. USB KEYBOARD CABLE CONNECTOR (MALE)................................................................. C-16
FIGURE D-1. COMPAQ/NVIDIA VANTA LT AGP GRAPHICS CARD (P/N 192174-002) LAYOUT.............D-1
FIGURE D-2. COMPAQ/NVIDIA VANTA LT GRAPHICS CARD BLOCK DIAGRAM .........................................D-2
FIGURE D-3. VGA MONITOR CONNECTOR, (FEMALE DB-15, AS VIEWED FROM REAR)..............................D-5
FIGURE E–1. COMPAQ/NVIDIA M64 AGP GRAPHICS CARD LAYOUT (COMPAQ P/N 179250)..................E-1
FIGURE E–2. COMPAQ/NVIDIA M64 AGP GRAPHICS CARD BLOCK DIAGRAM.........................................E-2
FIGURE E–3. VGA MONITOR CONNECTOR, (FEMALE DB-15, AS VIEWED FROM REAR)...............................E-5
FIGURE E–4. VIDEO INTERFACE CONNECTOR (26-PIN HEADER)................................................................E-6

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LIST OF TABLES
TABLE 1–1. ACRONYMS AND ABBREVIATIONS...........................................................................................1-3
TABLE 2-1. FEATURE DIFFERENCE MATRIX ...............................................................................................2-2
TABLE 2-2. CHIPSET COMPARISON ...........................................................................................................2-14
TABLE 2-3. SUPPORT COMPONENT FUNCTIONS ........................................................................................2-14
TABLE 2-4. GRAPHICS SUBSYSTEM COMPARISON ....................................................................................2-16
TABLE 2-5. ENVIRONMENTAL SPECIFICATIONS.........................................................................................2-17
TABLE 2-6. ELECTRICAL SPECIFICATIONS.................................................................................................2-17
TABLE 2-7. PHYSICAL SPECIFICATIONS.....................................................................................................2-18
TABLE 2-8. DISKETTE DRIVE SPECIFICATIONS..........................................................................................2-18
TABLE 2-9. 48X CD-ROM DRIVE SPECIFICATIONS ..................................................................................2-19
TABLE 2-10. HARD DRIVE SPECIFICATIONS..............................................................................................2-19
TABLE 3–1. CELERON PROCESSOR STATISTICAL COMPARISON ..................................................................3-2
TABLE 3–2. PENTIUM III PROCESSOR STATISTICAL COMPARISON..............................................................3-3
TABLE 3–3. SPD ADDRESS MAP (SDRAM DIMM) ....................................................................................3-6
TABLE 3–4. HOST/PCI BRIDGE CONFIGURATION REGISTERS (GMCH, FUNCTION 0)..................................3-8
TABLE 4-1. PCI DEVICE CONFIGURATION ACCESS.....................................................................................4-4
TABLE 4-2. SYSTEM BOARD PCI DEVICE IDENTIFICATION.........................................................................4-5
TABLE 4-3. PCI BUS MASTERING DEVICES................................................................................................4-6
TABLE 4-4. LPC BRIDGE CONFIGURATION REGISTERS (ICH, FUNCTION 0) ................................................4-8
TABLE 4-5. PCI BUS CONNECTOR PINOUT.................................................................................................4-9
TABLE 4-6. PCI/AGP BRIDGE CONFIGURATION REGISTERS (MCH, FUNCTION 1) ....................................4-13
TABLE 4-7. AGP BUS CONNECTOR PINOUT ..............................................................................................4-14
TABLE 4-8. MASKABLE INTERRUPT PRIORITIES AND ASSIGNMENTS.........................................................4-16
TABLE 4-9. MASKABLE INTERRUPT CONTROL REGISTERS........................................................................4-17
TABLE 4-10. DEFAULT DMA CHANNEL ASSIGNMENTS............................................................................4-19
TABLE 4-11. DMA PAGE REGISTER ADDRESSES......................................................................................4-20
TABLE 4-12. DMA CONTROLLER REGISTERS...........................................................................................4-21
TABLE 4-13. CLOCK GENERATION AND DISTRIBUTION.............................................................................4-22
TABLE 4-14. CONFIGURATION MEMORY (CMOS) MAP ...........................................................................4-24
TABLE 4-15. SYSTEM BOOT/ROM FLASH STATUS LED INDICATIONS......................................................4-35
TABLE 4-16. SYSTEM OPERATIONAL STATUS LED INDICATIONS ..............................................................4-36
TABLE 4-17. SYSTEM I/O MAP.................................................................................................................4-38
TABLE 4-18. 82801 ICH GPIO REGISTER UTILIZATION............................................................................4-39
TABLE 4-19 LPC47B357 CONTROL REGISTERS........................................................................................4-40
TABLE 4-20. LPC47B357 GPIO REGISTER UTILIZATION..........................................................................4-41
TABLE 5–1. IDE PCI CONFIGURATION REGISTERS.....................................................................................5-2
TABLE 5–2. IDE BUS MASTER CONTROL REGISTERS .................................................................................5-2
TABLE 5–3. 40-PIN PRIMARY IDE CONNECTOR PINOUT ............................................................................5-3
TABLE 5–4. DISKETTE DRIVE CONTROLLER CONFIGURATION REGISTERS..................................................5-5
TABLE 5–5. DISKETTE DRIVE INTERFACE CONTROL REGISTERS ................................................................5-5
TABLE 5–6. 34-PIN DISKETTE DRIVE CONNECTOR PINOUT.........................................................................5-7
TABLE 5–7. DB-9 SERIAL CONNECTOR PINOUT..........................................................................................5-8
TABLE 5–8. SERIAL INTERFACE CONFIGURATION REGISTERS.....................................................................5-9
TABLE 5–9. SERIAL INTERFACE CONTROL REGISTERS................................................................................5-9
TABLE 5–10. PARALLEL INTERFACE CONFIGURATION REGISTERS............................................................5-12
TABLE 5–11. PARALLEL INTERFACE CONTROL REGISTERS .......................................................................5-12
TABLE 5–12. DB-25 PARALLEL CONNECTOR PINOUT..............................................................................5-13

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First Edition - August 2000
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TABLE 5–13. 8042-TO-KEYBOARD COMMANDS ......................................................................................5-15
TABLE 5–14. KEYBOARD INTERFACE CONFIGURATION REGISTERS ..........................................................5-16
TABLE 5–15. CPU COMMANDS TO THE 8042..........................................................................................5-18
TABLE 5–16. KEYBOARD/POINTING DEVICE CONNECTOR PINOUT...........................................................5-19
TABLE 5–17. USB INTERFACE CONFIGURATION REGISTERS ....................................................................5-22
TABLE 5–18. USB CONTROL REGISTERS..................................................................................................5-22
TABLE 5–19. USB CONNECTOR PINOUT ..................................................................................................5-23
TABLE 5–20. USB CABLE LENGTH DATA ................................................................................................5-23
TABLE 5–21. AC’97 AUDIO CONTROLLER PCI CONFIGURATION REGISTERS............................................5-28
TABLE 5–22. AC’97 AUDIO CODEC CONTROL REGISTERS.......................................................................5-28
TABLE 5–23. AUDIO SUBSYSTEM SPECIFICATIONS...................................................................................5-29
TABLE 5–24. AOL EVENTS......................................................................................................................5-30
TABLE 5–25. REMOTE SYSTEM ALERT EVENTS .......................................................................................5-33
TABLE 6-1. INTEL GRAPHICS DISPLAY MODES...........................................................................................6-4
TABLE 6-2. 815-BASED GRAPHICS CONTROLLER PCI CONFIGURATION REGISTERS...................................6-5
TABLE 6-3. MONITOR POWER MANAGEMENT CONDITIONS........................................................................6-5
TABLE 6-4. DB-15 MONITOR CONNECTOR PINOUT....................................................................................6-6
TABLE 8-1. BOOT BLOCK CODES..................................................................................................................8-2
TABLE 8-2. BOOT ERROR CODES..................................................................................................................8-5
TABLE 8-3. SETUP UTILITY FUNCTIONS......................................................................................................8-6
TABLE 8-4. CLIENT MANAGEMENT FUNCTIONS (INT15)..........................................................................8-12
TABLE 8-5. PNP BIOS FUNCTIONS...........................................................................................................8-15
TABLE 8-6. APM BIOS FUNCTIONS...........................................................................................................8-20
TABLE A–1. BEEP/KEYBOARD LED CODES..............................................................................................A-1
TABLE A–2. POWER-ON SELF TEST (POST) MESSAGES ...........................................................................A-2
TABLE A–3. SYSTEM ERROR MESSAGES ................................................................................................... A-3
TABLE A–4. MEMORY ERROR MESSAGES................................................................................................. A-4
TABLE A–5. KEYBOARD ERROR MESSAGES..............................................................................................A-4
TABLE A–6. PRINTER ERROR MESSAGES ..................................................................................................A-5
TABLE A–7. VIDEO (GRAPHICS) ERROR MESSAGES..................................................................................A-5
TABLE A–8. DISKETTE DRIVE ERROR MESSAGES ..................................................................................... A-6
TABLE A–9. SERIAL INTERFACE ERROR MESSAGES .................................................................................. A-6
TABLE A–10. SERIAL INTERFACE ERROR MESSAGES ................................................................................ A-7
TABLE A–11. SYSTEM STATUS ERROR MESSAGES....................................................................................A-8
TABLE A–12. HARD DRIVE ERROR MESSAGES .........................................................................................A-8
TABLE A–13. HARD DRIVE ERROR MESSAGES .........................................................................................A-9
TABLE A–14. HARD DRIVE MESSAGES ..................................................................................................... A-9
TABLE A–15. AUDIO ERROR MESSAGES ................................................................................................. A-10
TABLE A–16. DVD/CD-ROM DRIVE ERROR MESSAGES .......................................................................A-10
TABLE A–17. NETWORK INTERFACE ERROR MESSAGES .........................................................................A-10
TABLE A–18. SCSI INTERFACE ERROR MESSAGES.................................................................................A-11
TABLE A–19. POINTING DEVICE INTERFACE ERROR MESSAGES ............................................................. A-11
TABLE C–1. KEYBOARD-TO-SYSTEM COMMANDS .................................................................................. C-11
TABLE C–2. KEYBOARD SCAN CODES..................................................................................................... C-12
TABLE D-1. NVIDIA VANTA LT 2D GRAPHICS DISPLAY MODES ..............................................................D-3
TABLE D-2. MONITOR POWER MANAGEMENT CONDITIONS......................................................................D-4
TABLE D-3. DB-15 MONITOR CONNECTOR PINOUT ..................................................................................D-5

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First Edition –- August 2000
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TABLE E–1. NVIDIA M64 2D GRAPHICS DISPLAY MODES.........................................................................E-3
TABLE E–2. MONITOR POWER MANAGEMENT CONDITIONS.......................................................................E-4
TABLE E–3. DB-15 MONITOR CONNECTOR PINOUT...................................................................................E-5
TABLE E–4. MULTIMEDIA INTERFACE CONNECTOR PINOUT.......................................................................E-6

Technical Reference Guide
Compaq Deskpro EX Series of Personal Computers
Review Copy - August 2000
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Chapter 1
INTRODUCTION
1. Chapter 1 INTRODUCTION
1.1 ABOUT THIS GUIDE
This guide provides technical information about the Compaq Deskpro EX Series of Personal
Computers. This document includes information regarding system design, function, and features
that can be used by programmers, engineers, technicians, and system administrators.
This guide and any applicable addendums are available online at the following location:
http://www.compaq.com/support/techpubs/technical_reference_guides/index.html
1.1.1 USING THIS GUIDE
The chapters of this guide primarily describe the hardware and firmware elements and primarily
deal with the system board and the power supply assembly. The appendices contain general
information about standard peripheral devices such as the keyboard.
1.1.2 ADDITIONAL INFORMATION SOURCES
For more information on chipset components mentioned in this guide refer to the indicated
manufacturers’ documentation, which may be available at the following online sources:
♦Compaq Computer Corporation: http://www.compaq.com
♦Intel Corporation: http://www.intel.com
♦Standard Microsystems Corporation: http://www.smsc.com
1.2 MODEL NUMBERING CONVENTION
The model numbering convention for Compaq Deskpro EX units is as follows:
EXX/XNNN/NNc/N/NNNxxx
NIC/Modem: n = NIC, m = modem
Graphics: blank = integrated, a = AIMM, v = nVIDIA
Removable storage: b = CD/CDRW, c = CD, d = DVD, r = CDRW, z = ZIP
Memory (in MB)
OS type (9 = Dual install Win95/98, 4 = Win NT 4.0, 6 = Dual install Win NT/2000)
Chipset type (c = 815)
Hard drive size (in GB)
Processor speed (in MHz)
Processor type: C = Celeron; P = Pentium
Form factor: D = Desktop, M = Minitower
Deskpro series

Chapter 1 Introduction
Compaq Deskpro EX Series of Personal Computers
Review Copy – August 2000
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1.3 NOTATIONAL CONVENTIONS
1.3.1 VALUES
Hexadecimal values are indicated by a numerical or alpha-numerical value followed by the letter
“h.”Binary values are indicated by a value of ones and zeros followed by the letter “b.”
Numerical values that have no succeeding letter can be assumed to be decimal.
1.3.2 RANGES
Ranges or limits for a parameter are shown using the following methods:
Example A: Bits <7..4> = bits 7, 6, 5, and 4.
Example B: IRQ3-7, 9 = IRQ signals 3 through 7, and IRQ signal 9
1.3.3 SIGNAL LABELS
Signal names are indicated using abbreviations, acronyms, or, if possible, the full signal name in
all capital letters. Signals that are meant to be active (asserted) low are indicated with a dash
immediately following the name.
1.3.4 REGISTER NOTATION AND USAGE
This guide uses standard Intel naming conventions in discussing the microprocessor’s (CPU)
internal registers. Registers that are accessed through programmable I/O using an indexing scheme
are indicated using the following format:
03C5.17h
Index port
Data port
In the example above, register 03C5.17h is accessed by writing the index port value 17h to the
index address (03C4h), followed by a write to or a read from port 03C5h.
1.3.5 BIT NOTATION
Bit values are labeled with bit <0> representing the least-significant bit (LSb) and bit <7>
representing the most-significant bit (MSb) of a byte. Bytes, words, double words, and quad words
are typically shown with most-significant portions on the left or top and the least-significant
portions on the right or bottom respectively.