Dell OptiPlex 100-Mbps User Manual

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Information in this document is subject to change without notice.

1996 Dell Computer Corpora tion. All rights reserved.



Reproduction in any m an ner whatsoever without the writt en perm ission of Dell Computer Co rporation is strictly forbidd en .
Trademarks used in this text: Dell, the DELL logo, and Opt iPlex are registered trademarks of Dell Computer Corporation; Intel and Pentium are registered trademarks

of Intel Corporation; Microsoft, MS-DOS, Windows, and Windows NT are registered trademarks of Microsoft Corporation; Novell and NetW are are registered trademarks
of Novell, Inc.; IBM is a registered tra de m ark of International Business Machi nes Corporation; 3Com is a registe red trademark of 3Com Corporation.

Other trademarks and tr ade names may be used in this document to refer to either the ent it ie s claiming the marks and names or their products. Dell Compu te r
Corporation disclai m s a ny proprietary interest in trademarks and trade names othe r than its own.

December 1996 P/N 84577

Contents

Chapter 1

System Overview. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-1

System Features . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-2

Dual-Processor Capability . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-5

Advanced Expansion Subsystem . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-5

Hard-Disk Drive Options . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-6

Enhanced Dual-Interface EIDE Subsystem . . . . . . . . . . . . . . . . . . . . . . . 1-6

Audio Controller. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-6

PCI Video Card. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-6

NIC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-7

USB. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-7

Desktop Chassis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-7

Thermal Monitoring . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-7

System Unit. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-8

System Power Supply. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-8

Pin Assignments for the DC Power Connectors. . . . . . . . . . . . . . . . . 1-8

DC Power Distribution . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-10

System Board Layout . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-12

Video Memory . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-12

Main Memory . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-13

System Board Jumpers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-13

Interrupt Assignments. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-14

DMA Channel Assignments. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-15

Technical Specifications. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-16

v

Chapter 2

Basic Troubleshooting . . . . . . . . . . . . . . . . . . . . . . . . . . 2-1

Initial User Contact . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-1

External Visual Inspection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-2

Observing the Boot Routine. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-3

Internal Visual Inspection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-4

Eliminating Resource Conflicts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-5

Running the Diskette-Based Diagnostics. . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-5

Getting Help. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-6

Chapter 3

Beep Codes and Error Messages . . . . . . . . . . . . . . . . . . 3-1

POST Beep Codes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-1

System Error Messages . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-3

Chapter 4

Removing and Replacing Parts . . . . . . . . . . . . . . . . . . . 4-1

Recommended Tools . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-1

Precautionary Measures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-2

Floor Stand. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-3

System Unit Cover . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-4

Eject, Power, and Reset Buttons . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-5

Front-Panel Inserts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-6

Indicator Card. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-7

Speaker. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-8

Drives . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-9

Drives in the Drive Cage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-10

Hard-Disk Drives . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-12

System Power Supply. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-14

Microprocessor Fan . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-15

System Board Components . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-16

Expansion Cards. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-17

Expansion-Card Cage. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-17

Expansion Card . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-18

Riser Board. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-19

DIMMs. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-20

Microprocessor/Heat Sink Assembly. . . . . . . . . . . . . . . . . . . . . . . . . . . 4-21

Terminator or Add-In Card . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-23

vi

Terminator Card . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-23

Add-In Card . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-24

System Battery . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-25

System Board . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-26

Appendix A

System Setup Program. . . . . . . . . . . . . . . . . . . . . . . . . . A-1

System Setup Screens. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .A-2

Index

Figures

Figure 1-1. System Unit Orientation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-3

Figure 1-2. Front-Panel Features . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-4

Figure 1-3. Internal View . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-4

Figure 1-4. Riser-Board Expansion-Card Connectors . . . . . . . . . . . . . . . . 1-5

Figure 1-5. DC Power Connector P1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-9

Figure 1-6. DC Power Connectors P2, P3, P4, P5, and P6. . . . . . . . . . . . . 1-9

Figure 1-7. DC Power Connectors P7 . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-10

Figure 1-8. DC Power Cables. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-10

Figure 1-9. Power Distribution. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-11

Figure 1-10. System Board Components . . . . . . . . . . . . . . . . . . . . . . . . . . 1-12

Figure 1-11. System Board Jumpers. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-13

Figure 4-1. Floor Stand Removal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-3

Figure 4-2. System-Unit Cover Removal . . . . . . . . . . . . . . . . . . . . . . . . . . 4-4

Figure 4-3. Padlock Removal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-4

Figure 4-4. Eject, Power, and Reset Button Removal . . . . . . . . . . . . . . . . 4-5

Figure 4-5. Front-Panel Insert Removal . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-6

Figure 4-6. Indicator Card Removal. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-7

Figure 4-7. Speaker Removal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-8

Figure 4-8. Drive Hardware . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-9

Figure 4-9. 3.5-Inch Diskette Drive Removal . . . . . . . . . . . . . . . . . . . . . 4-10

Figure 4-10. 5.25-Inch Drive Removal. . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-11

Figure 4-11. Hard-Disk Drive Bracket Removal . . . . . . . . . . . . . . . . . . . . 4-12

Figure 4-12. Hard-Disk Drive Removal . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-13

Figure 4-13. Power Supply Removal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-14

Figure 4-14. Microprocessor Fan Removal . . . . . . . . . . . . . . . . . . . . . . . . 4-15

Figure 4-15. System Board Components . . . . . . . . . . . . . . . . . . . . . . . . . . 4-16

vii

Figure 4-16. Expansion-Card Cage Removal . . . . . . . . . . . . . . . . . . . . . . 4-17

Figure 4-17. Expansion-Card Removal . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-18

Figure 4-18. Riser Board Removal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-19

Figure 4-19. DIMM Removal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-20

Figure 4-20. DIMM Installation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-20

Figure 4-21. Microprocessor Securing Clip. . . . . . . . . . . . . . . . . . . . . . . . 4-21

Figure 4-22. Microprocessor Removal. . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-22

Figure 4-23. Terminator Card Removal. . . . . . . . . . . . . . . . . . . . . . . . . . . 4-23

Figure 4-24. Add-In Card Removal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-24

Figure 4-25. System Battery Removal. . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-25

Figure 4-26. System Board Removal. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-26

Figure A-1. System Setup Screens . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .A-2

Tables

Table 1-1. DC Voltage Ranges. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-8

Table 1-2. Jumper Descriptions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-14

Table 1-3. Interrupt Assignments . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-14

Table 1-4. DREQ Line Assignments . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-15

Table 1-5. Technical Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-16

Table 3-1. POST Beep Codes. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-1

Table 3-2. System Error Messages . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-4

Table A-1. System Setup Categories. . . . . . . . . . . . . . . . . . . . . . . . . . . . .A-3

viii

ix

ead This First

R

A prerequisite for using this manual to service Dell computer systems is a
basic knowledge of IBM®-compatible PCs and prior training in IBM­compatible PC troubleshooting techniques. In addition to information
provided in this manual and th e User’s Guide that c ame with the system, Dell
provides the Diagnostics and T r oubleshooting Guide for troubleshooting pro­cedures and instructions on using the Dell diagnostics to test the computer
system.

arnings, Cautions, and Notes

W

Throughout this manual, there may be blocks of text printed in bold type or in
italic type. These blocks are warnings, cautions, and notes, and they are used as
follows:

WARNING: A WARNING indicates the potential for bodily harm and pro­vides instructions for how to avoid the problem.

CAUTION: A CAUTION indicates either potential damage to hardware or
loss of data and provides instructions for how to avoid the problem.

NOTE: A NOTE provides helpful information about using the computer system.

x

Chapter 1

System Overview

his service manual covers the Dell

T

able desktop systems, which use the Intel® Pentium® Pro family of
microprocessors. These Dell systems incorporate the high-performance PCI
local bus as well as the ISA expansion bus. These buses are built into the system
board, which also integrates a 3.3-V Pentium Pro microprocessor and all other
elements of the basic computer system.

The Pentium Pro microprocessor contains a built-in clock multiplier circuit,
which increases the microprocessor’ s internal operating freque ncy to a m ultiple
of the system clock frequency. The microprocessors for each of these systems
and their operating frequencies are as follows:

Dell OptiPlex GXpro 180 systems — 180 MHz derived from a system clock

•

frequency of 60 MHz
Dell OptiPlex GXpro 200 systems — 200 MHz derived from a system clock

•

frequency of 66 MHz

Dell OptiPlex GXpro systems contain either an integrated 10-Mbps or
10/100-Mbps 3Com® NIC, both of which are covered in this document.

®

OptiPlex® GXpro high-speed, upgrad-

System Overvi ew 1-1

S

ystem Features

In addition to the standard features found in a traditional personal computer , the
Dell OptiPlex GXpro desktop systems include the following new and/or
advanced features:

Dual-processor capability.

•

Advanced combination ISA and PCI expansion subsystem.

•

Plug and Play capability.

•

Enhanced dual-interface EIDE subsystem.

•

16-bit integrated audio controller.

•

PCI video card.

•

Integrated 10-Mbps or 10/100-Mbps Ethernet NIC.

•

Integrated Universal Serial Bus (USB) controller with two USB-compliant

•

connectors (included on systems containing the 10/100-Mbps NIC).
Desktop chassis.

•

Thermal monitoring.

•

Main system memory consisting of 16 to 512 MB of high-speed EDO

•

DIMMs that provide ECC functionality when used with the Intel 82440FX
PCIset.

SMART support-compliant hard-disk drives and SMART support in the

•

system BIOS, which warns you at system start-up if a hard-disk drive has
become unreliable.

Quick tests feature in the diskette-based diagnostics (for more information

•

about Run Quick Tests, see “Running the Diskette-Based Diagnostics” in
Chapter 2).

All of these features (except the Run Quick Tests feature described in Chap­ter 2) are briefly described in this chapter . For a complete list of system features,
see “Technical Specifications” found later in this chapter.

When following the text in this manual, assume that the location or direction
relative to the system unit is as shown in Figure 1-1.

1-2 Dell OptiPlex GX

pro

Systems Service Manual

back of system unit

left side

front of system unit

right side

Figure 1-1. System Unit Orientation

CAUTION: To avoid possible data or file structure corruptions, the
front-panel reset button should be used only when the system cannot be
rebooted by pressing <Ctrl><Alt><Del>. Before you use the reset button
to initiate a hardware reset, close any open application programs and
files if possible.

System Overvi ew 1-3

power button

power indicator

reset button

hard-disk drive access indicator

Figure 1-2. Front-Panel Features

power supply

AC power
receptacle

voltage
selection switch

parallel port connector

serial port 1 connector

mouse connector

keyboard connector

serial port 2 connector

USB connector (2)

diskette/tape drive
interface cable

DC power cable

NIC connector

video connector

3.5-inch drive

microphone jack

speaker-out jack

drive cage

hard-disk drive
bracket

system board

expansion-card
cage

chassis

card-slot openings

line-in jack

1-4 Dell OptiPlex GX

Figure 1-3. Internal View

pro

Systems Service Manual

Dual-Processor Capability

With the installation of a microprocessor add-in card in the terminator card slot,
the system unit becomes a dual-processing system. The add-in card’s micro­processor must have the same frequency and cache size as the system board’s
microprocessor. In order to take advantage of two processors, dual-processing
systems must have multiprocessing operating systems, such as the Microsoft®
Windows NT® 3.5x, Win dows NT 4.0, and Novell® NetWare® SMP (symmetric
multiprocessing) operating systems. The microprocessor chip s on both the system
board and the processor card are replaceable.

Advanced Expansion Subsystem

The computer system offers advanced expansion subsystems that can support a
mixture of traditional ISA expansion cards (called legacy cards), Plug and Play
ISA expansion cards, and PCI expansion cards. The ISA Configuration Utility
(ICU) included with the system provides a means of avoiding resource conflicts
that might arise from such an arrangement.

After all legacy cards have been configured with the ICU, the system automati­cally assigns any required memory space, IRQ lines, and DMA channels to any
installed Plug and Play ISA expansion cards and PCI expansion cards the next
time the system is rebooted. Chapter 4, “Using the ISA Configuration Utility,”
in the User’s Guide describes the ICU and pr ovides in structi ons for using it to co n-
figure the system.

The five expansion slots include two ISA expansion-card connectors and five
PCI expansion-card connectors. (Two PCI expansion-card connectors and the
two ISA expansion-card connectors share a single expansion slot, resulting in a
total of five expansion slots.) The expansion-card connectors are located on a
riser board (see Figure 1-4).

ISA2

PCI 5

ISA1

JMIDI connector

PCI1

JHDLED connector

Figure 1-4. Riser-Board Expansion-Card Connectors

System Overvi ew 1-5

Hard-Disk Drive Options

The hard-disk drive bracket is located next to the drive bays at the front of the
system unit. The system unit can contain up to two, one-inch-high, hard-disk
drives or one, 1.6-inch-high, half-height and one, one-inch-high, hard-disk
drive.

Enhanced Dual-Interface EIDE Subsystem

The enhanced dual-interface EIDE subsystem supports two EIDE interfaces
(primary and secondary), each of which can support up to two EIDE devices.
The EIDE controller resides on the high-speed PCI local bus.

The primary EIDE interface (IDE1) provides support for up to two high-

•

performance EIDE devices. The system’s boot drive should be connected to
the primary EIDE interface.

The secondary EIDE interface (IDE2) also provides support for up to two

•

high-performance EIDE devices, typically EIDE tape drives or CD-ROM
drives.

NOTE: The externally accessible drive bays at the front of the system unit are
normally used for diskette drives, CD-ROM drives, and/or tape drives. Hard­disk drives should be installed in the internal hard-disk drive bracket described
in the previous subsection, “H a rd-Di sk D r i v e O p t i on s . ” F or d e t ai l e d in f o r ma t i o n
about the data storage subsystem, see Chapter 9, “Installing Drives,” in the User’s
Guide.

Audio Controller

The system board has a built-in 16-bit Creative Labs V iBRA 16 audio controlle r
chip and connectors on the back panel for connecting the system unit to external
audio devices (speakers, microphone). The controller supports all the sound
functions found on the Sound Blaster expansion card from Creative Laborato­ries, Inc.

Chapter 6, “Using the Integrated Audio Controller,” in the User’s Guide pro-
vides instructions for connecting the system to external audio devices and
configuring the integrated audio controller to avoid resource conflicts.

PCI Video Card

The video subsystem consists of a high-speed, high-resol ution video adapter card
installed in one of the bottom two PCI expansion-card connectors (PCI1 or PCI2).
Because the video adapter card connects to the PCI local bus rather than to the
ISA-compatible system bus, communication between the video subsystem and
the microprocessor is much faster. The PCI local bus operates at a frequency of
30 or 33 MHz as opposed to the 8-MHz operating frequency of the ISA bus.

NOTE: Some users may use an ISA video adapter card.

1-6 Dell OptiPlex GX

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Systems Service Manual

NIC

GXpro systems contain either an integrated 10-Mbps or 10/100-Mbps 3Com
NIC. GXpro systems containing the 10-Mbps Ethernet NIC have a built-in inte-
grated 3Com 3C915 NIC chip. GXpro systems containing the 10/100-Mbps
Ethernet NIC have a built-in integrated 3Com 3C916 Ethernet NIC chip. The
NIC subsystem connects to the Ethernet network through a single RJ45 connec­tor on the back panel of the computer.

The 10/100-Mbps NIC supports a 10-Mbps direct connection to either a cate­gory-3 or a category-5 ethernet cable. When the NIC operates in the
100-Mbps mode, a category-5 ethernet cable must be used.

GXpro systems with the 10/100-Mbps NIC also contain two USB connectors.
Thus, to determine whether a particular system contains the 10/100-Mbps NIC,
look for one of the following indications:

USB connectors next to the NIC connector on the computer’s back panel

•

The message USB Enhanced displayed during the boot routine

•

A USB category on page 2 of the System Setup

•

If any of these indications are present, your system has the 10/100-Mbps NIC.
Chapter 5, “Using the Network Interface Controller,” in the User’s Guide pro-

vides instructions for connecting the system to, and configuring it for use on, an
Ethernet network.

USB

USB capability simplifies connection of peripheral devices such as mice, print­ers, and computer speakers. The USB connectors on your computer’s back
panel provide a single connection point for multiple USB-compliant devices.
USB-compliant devices can also be connected and disconnected while the sys­tem is running.

NOTE: USB capability is available only on systems with the 10/100-Mbps NIC.

Desktop Chassis

The system unit can be set horizontally or vertically, when used with the floor
stand provided with the system. The floor stand attaches to the left side of the
system.

Thermal Monitoring

The primary and, if installed, secondary microprocessors have a thermal sensor
that monitors the processor’ s temperature. If the critical threshold is exceeded, a
system alarm triggers a system management interrupt (SMI), which alerts the
BIOS. The power indicator flashes, and a message appears on the monitor to
alert the user that the system will shut down in an orderly manner, preventing
the loss of data.

System Overvi ew 1-7

SMART Support

The system has SMART-compliant hard-disk drives and SMART support in the
system BIOS, which warns you at system start-up if a hard-disk drive has
become unreliable.

S

ystem Unit

The following subsections provide service-related information about the system
unit.

System Power Supply

The 230-W system power supply can operate from an AC power source of
115 VAC at 60 Hz or 230 VAC at 50 Hz. The system power supply provides the
DC operating voltages and currents listed in Table 1-1.

NOTE: The power supply produces DC voltages only under its loaded condi­tion. Therefore, when you measure these voltages, the DC power connectors
must be connected to their corr esponding power input connectors on the s ystem
board or drives.

.

Table 1-1. DC Voltage Ranges

Voltage Range

Maximum Output
Current

1

+3.3 VDC +3.15 to +3.45 VDC 14.0 A
+5 VDC +4.75 to +5.25 VDC 29.0 A
+12 VDC +11.40 to +12.60 VDC

6.0 A
–12 VDC –10.80 to –13.20 VDC 0.3 A
–5 VDC –4.50 to –5.50 VDC 0.3 A

+5 VFP

1

Maximum continuous DC output power shall not exceed 230 W. Maximum combined

2

VFP (volts flea power) — sometimes called “standby power.”

.

2

load on +5 VDC and +3.3 VDC shall not exceed 170 W.

+4.75 to +5.25 VDC 10 mA

Pin Assignments for the DC Power Connectors

The power-supply output voltages can be measured at the back (wire side) of
the connectors without disconnecting them. The following illustrations show
the wire side of the connectors.

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–5 VDC (white)

common (black)

common (black)
common (black)

1

PSON#

(gray)

11

12 13 14 15 16 17 18 19 20

+5 VDC (red)

+5 VDC (red)
+5 VDC (red)

2

(brown)

TFSC

+5 VDC (red)

P1

1

234 5678 910

+5 VDC (red)

common (black)

+5 VDC (red)

common (black)

3

PWRGOOD

1

Pin 11 — PSON# should measure between +4 and +5 VDC except when the power button

(orange)

common (black)
common (black)

–12 VDC (blue)
+12 VDC (yellow)
+5 VFP (purple)

on the front panel is pressed, taking PSON# to its active-low state.

2

Pin 19 — Thermal fan-speed control (TFSC) is a power-supply input signal used to control

power-supply fan speed in specia l applications.

3

Pin 5 — PWRGOOD should measure between +4 and +5 VDC when the po wer supply is on

and operating to indicate that all power-supply output voltages are within ranges specified
in Table 1-1.

Figure 1-5. DC Power Connector P1

P2, P3,
P5, P6

1234

+5 VDC (red)
common (black)
common (black)
+12 VDC (yellow)

P4

1234

+12 VDC (yellow)
common (black)
common (black)
+5 VDC (red)

Figure 1-6. DC Power Connectors P2, P3, P4, P5, and P6

System Overvi ew 1-9

P7

1234

5

6

+3.3 VDC (blue/white)

+3.3 VDC (blue/white)
+3.3 VDC (blue/white)

common (black)
common (black)
common (black)

Figure 1-7. DC Power Connector P7

DC Power Distribution

Figures 1-8 and 1-9 provide the following information about DC power
distribution:

Power-supply connector identification

•

Power cable connections for diskette, tape, CD-ROM, and hard-disk drives

•

Power distribution to sockets and connectors on the system board

•

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Figure 1-8. DC Power Cables

pro

Systems Service Manual

P5

P3

P6

P1

P4

P7

P2

system

power supply

PWRGOOD

P1

PSON#
+5 VFP
+5 VDC
–5 VDC
+12 VDC
–12 VDC

P7
+3.3 VDC

keyboard
controller

POWER1

PSON#
+5 VFP
+5 VDC
–5 VDC
+12 VDC
–12 VDC

POWER2

power

management

logic

+3 VDC

RTC/

NVRAM

system board

battery

RISER

+5 VDC
–5 VDC
+12 VDC
–12 VDC

+12 VDC

FAN

riser board

+5 VDC
+12 VDC
–12 VDC

+5 VDC
–5 VDC
+12 VDC
–12 VDC

PCI1
through
PCI5

ISA1,
ISA2

main memory

optional

drive

optional

drive

3.5-inch

diskette drive

internal

P2

P3

P4

P5

sockets

DIMM_A

DIMM_B

DIMM_C

DIMM_D

MICROPROCESSOR

hard-disk drive

P6

internal

hard-disk drive

2ND_CPU

Figure 1-9. Power Distribution

+2.1–3.5 VDC

+3.3 VDC

+2.1–3.5 VDC

+3.3 VDC

+5 VFP

+5 VDC

FUSE

+5 VDC

FUSE

+5 VDC

+5 VDC

processor
core regulator

PANEL

USB

KYBD

MOUSE

System Overvi ew 1-11

System Board Layout

The subsections that follow provide service-related information about the sys­tem board components.

microphone jack (NIC-IN)

speaker-out jack
(SPKR-OUT)

line-in jack (LINE-IN)

riser board power
connector (RSR PWR1)

riser board
connector (RISER)

riser board power
connector
(RSR PWR2)

secondary microprocessor
card (or terminator
card) connector (2ND_CPU)

NIC
connector
(ENET)

front of system unit

primary EIDE
interface connector (IDE1)

USB
connector
(USB)

serial port 2
connector
(SERIAL2)

jumpers

keyboard/mouse
connectors
(stacked)
(KYBD/MOUSE)

control panel
connector (PANEL)

serial port 1/parallel
port connectors (stacked)
(PARALLEL/SERIAL)

microprocessor fan
connector (FAN)

battery socket
(BATTERY)

DIMM sockets (4)
main power input

connector (POWER1)

microprocessor socket
(MICROPROCESSO R)

3.3-V power
input connectors
(POWER2)

CD-ROM
connector (CD_IN)

diskette/tape drive interface
connector (DSKT)

secondary EIDE interface
connector (IDE2)

Figure 1-10. System Board Components

Video Memory

See the documentation from the video card manufacturer that came with your
system for information on removing and replacing video-memory upgrade
chips.

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Main Memory

The four DIMM sockets on the system board can accommodate combinations
of 16-, 32-, 64-, and 128-MB DIMMs up to a total memory capacity of 512 MB.
The system is shipped with high-speed (60-ns) EDO DIMMs that provide ECC
functionality when used with the Intel 82440FX PCIset. EDO parity mode
DIMMs can be mixed, as follows:

Any socket can be populated or not. There is no requirement that one socket

•

be filled before the other, and empty sockets can be left between installed
DIMMs. Dell recommends populating the sockets in order from A to D.

Each DIMM socket does not have to contain DIMMs of the same size or

•

speed. DIMMs may be installed in any order.

See “DIMMs” in Chapter 4 for information on removing and replacing DIMMs.

System Board Jumpers

jumpered

unjumpered

Figure 1-11. System Board Jumpers

System Overvi ew 1-13

Table 1-2. Jumper Descriptions

Jumper Description

Default
Setting

PSWD Password enable/disable.

Jumper installed, activates
password feature.

BIOS Used for internal Dell

debug tool.

RSRVD4
RSRVD3
RSRVD2
RSRVD1

200MHZ Microprocessor speed. Installed if the micro-

180MHZ Microprocessor speed. Installed if the micro-

Reserved. Not installed (reserved, do not

Installed (password feature
enabled)

Not installed (reserved, do not

change)

change)

processor’s internal speed is
200 MHz, or else not
installed

processor’s internal speed is
180 MHz, or else not
installed

I

nterrupt Assignments

Table 1-3. Interrupt Assignments

IRQ Line Used By/Available

IRQ0 Generated by system timer.
IRQ1 Generated by keyboard controller to indicate that keyboard’s out-

put buffer is full.

IRQ2 Generated internally by interrupt controller to enable IRQ8

through IRQ15.

IRQ3
and
IRQ4

IRQ5 Available for use by expansion card unless this IRQ line is used

IRQ6 Generated by super I/O controller to indicate that diskette or tape

IRQ7 Generated by super I/O controller to indicate that device con-

Generated by super I/O controller to indicate that device con­nected to corresponding serial port requires service (IRQ3 for
COM2 or COM4; IRQ4 for COM1 or COM3).

by secondary parallel port.

drive requires service.

nected to parallel port requires service.

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Table 1-3. Interrupt Assignments

IRQ Line Used By/Available

IRQ8 Generated by keyboard controller for each tick of RTC.
IRQ9 Available for use by expansion card.
IRQ10 Available for use by expansion card.
IRQ11 Available for use by expansion card.
IRQ12 Generated by keyboard controller to indicate t hat mouse’s output

buffer is full.
IRQ13 Generated by math coprocessor to indicate coprocessor error.
IRQ14 Generated by device connected to primary EIDE port to indicate

that device requires service. If no EIDE devices are installed, this

line is available for other use.
IRQ15 Generated by device connected to secondary EIDE port to indi-

cate that device requires service. If no device is connected to

secondary EIDE port, IRQ15 is available for use by expansion

card.

(continued)

D

MA Channel Assignments

Table 1-4. DREQ Line Assignments

DREQ Line Used By/Available

DREQ0 Available
DREQ1 Available
DREQ2 Generated by super I/O controller to initiate DMA cycle for

attached diskette drive
DREQ3 Available
DREQ4 Generated by bus controller chip to activate second DMA con-

troller
DREQ5 Available (default) DMA on-board sound controller
DREQ6 Available
DREQ7 Available

System Overvi ew 1-15

T

echnical Specifications

Table 1-5. Technical Specifications

Microprocessor

Microprocessor type. . . . . . . . Intel Pentium Pro microprocessor

Microprocessor speed. . . . . . . 200 or 180 MHz

First-level cache . . . . . . . . . . . 16 KB

Second-level cache. . . . . . . . . 256 KB for 180 or 200 MHz; 512 KB for

200 MHz

Math coprocessor . . . . . . . . . . internal to the microprocessor

System Information

System chip set. . . . . . . . . . . . Intel Natoma 82440FX set

Data bus width . . . . . . . . . . . . 64 bits

Address bus width . . . . . . . . . 32 bits

Flash EPROM. . . . . . . . . . . . . 2 Mbits

Expansion Bus

Bus types . . . . . . . . . . . . . . . . PCI and ISA

Bus speed . . . . . . . . . . . . . . . . PCI: 30 MHz (180/60 processor); 33 MHz

(200/66 processor)
ISA: 7.5 MHz (180/60 processor); 8.25 MHz
(200/66 processor)

PCI expansion-card

connectors. . . . . . . . . . . . . . . . five (two PCI connectors share card-slot open-

ings with the two ISA connectors)

ISA expansion-card

connectors. . . . . . . . . . . . . . . . two (both ISA connectors share card-slot

openings with two of the PCI connectors)

ISA expansion-card

connector size. . . . . . . . . . . . . 98 pins

ISA expansion-card connector

data width (maximum) . . . . . . 16 bits

PCI expansion-card

connector size. . . . . . . . . . . . . 120 pins

PCI expansion-card connector

data width (maximum) . . . . . . 32 bits

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