Intel D845GBV Technical manual

Product Supplement Document
for the
Intel®Desktop Board D845GBV
A companion document to the Technical Product
Specification for Intel®Desktop Boards
using the Intel®845G Chipset
April 2002
Order Number: A85839-001
Intel®Desktop Boards using the Intel®845G Chipset may contain design defects or errors known as errata that may cause the product to deviate from published specifications.
Current characterized errata are documented in the Specification Update for Intel Desktop Boards using the Intel 845G Chipset.

Revision History
Revision Revision History Date
-001 First release of the Product Supplement Document for the Intel®Desktop
Board D845GBV.
April 2002
This document applies to only the standard Intel Desktop Board D845GBV with BIOS identifier
RG84510.86A.
Changes to this specification will be published in the Specification Update for Intel Desktop
Boards using the Intel®845G Chipset before being incorporated into a revision of this document.
INFORMATION IN THIS DOCUMENT IS PROVIDED IN CONNECTION WITH INTEL®PRODUCTS. EXCEPT AS
PROVIDED IN INTEL’S TERMS AND CONDITIONS OF SALE FOR SUCH PRODUCTS, INTEL ASSUMES NO LIABILITY
WHATSOEVER, AND INTEL DISCLAIMS ANY EXPRESS OR IMPLIED WARRANTY, RELATING TO SALE AND/OR USE
OF INTEL PRODUCTS INCLUDING LIABILITY OR WARRANTIES RELATING TO FITNESS FOR A PARTICULAR
PURPOSE, MERCHANTABILITY, OR INFRINGEMENT OF ANY PATENT, COPYRIGHT, OR OTHER INTELLECTUAL
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rights that relate to the presented subject matter. The furnishing of documents and other materials and information does
not provide any license, express or implied, by estoppel or otherwise, to any such patents, trademarks, copyrights, or other
intellectual property rights.
Intel products are not intended for use in medical, life saving, or life sustaining applications or for any other application in
which the failure of the Intel product could create a situation where personal injury or death may occur.
Intel may make changes to specifications, product descriptions, and plans at any time, without notice.
The Intel Desktop Board D845GBV may contain design defects or errors known as errata that may cause the product to
deviate from published specifications. Current characterized errata are available on request.
Contact your local Intel sales office or your distributor to obtain the latest specifications before placing your product order.
Copies of documents which have an ordering number and are referenced in this document, or other Intel literature, may be
obtained from:
Intel Corporation
P.O. Box 5937
Denver, CO 80217-9808
or call in North America 1-800-548-4725, Europe 44-0-1793-431-155, France 44-0-1793-421-777,
Germany 44-0-1793-421-333, other Countries 708-296-9333.
Intel, Pentium, and Celeron are registered trademarks of Intel Corporation or its subsidiaries in the United States and other
countries.
†Other names and brands may be claimed as the property of others.
Copyright 2002, Intel Corporation. All rights reserved.

iii
Preface
This Product Supplement Document specifies the major components, layout, connectors, and
environmental requirements for the Intel Desktop Board D845GBV.
Intended Audience
The document is intended to provide detailed, technical information about the Intel Desktop Board
D845GBV and its components to the vendors, system integrators, and other engineers and
technicians who need this level of information. It is specifically not intended for general
audiences.
What This Document Contains
As stated on the cover, this is a companion document to the Technical Product Specification for
Intel Desktop Boards using the Intel 845G Chipset. The Technical Product Specification (order
number: A81229-001) is more general in nature, describing features common to multiple Desktop
Boards that use the Intel 845G chipset. This document describes features specific (though not
necessarily exclusive) to the Intel Desktop Board D845GBV.
Chapter Description
1 An overview of the features of the Intel Desktop Board D845GBV.
2 A description of the features specific to this product. This chapter also includes
drawings of the Desktop Board showing the locations of connectors.
3 Describes the regulatory compliance information specific to the Intel Desktop Board
D845GBV.
Typographical Conventions
This section contains information about the conventions used in this specification. Not all of these
symbols and abbreviations appear in all specifications of this type.
Notes, Cautions, and Warnings
✏ NOTE
Notes call attention to important information.

Product Supplement Document for the Intel Desktop Board D845GBV
iv
# INTEGRATOR’S NOTES
Integrator’s notes are used to call attention to information that may be useful to system
integrators.
CAUTION
Cautions are included to help you avoid damaging hardware or losing data.
WARNING
Warnings indicate conditions, which if not observed, can cause personal injury.
Other Common Notation
# Used after a signal name to identify an active-low signal (such as USBP0#).
(NxnX) When used in the description of a component, N indicates component type, xn are the relative
coordinates of its location on the Desktop Board, and X is the instance of the particular part at
that general location. For example, J5J1 is a connector, located at 5J. It is the first connector
in the 5J area.
GB Gigabyte (1,073,741,824 bytes)
GB/sec Gigabytes per second
KB Kilobyte (1024 bytes)
Kbit Kilobit (1024 bits)
kbits/sec 1000 bits per second
MB Megabyte (1,048,576 bytes)
MB/sec Megabytes per second
Mbit Megabit (1,048,576 bits)
Mbit/sec Megabits per second
xxh An address or data value ending with a lowercase h indicates a hexadecimal value.
x.x V Volts. Voltages are DC unless otherwise specified.
†This symbol is used to indicate third-party brands and names that are the property of their
respective owners.

v
Contents
1Overview
1.1 Feature Summary........................................................................................................ 7
1.2 Online Support ............................................................................................................ 8
1.3 Footnote Cross Reference........................................................................................... 9
1.4 Board Layout ..............................................................................................................10
2Product-Specific Features
2.1 Processor Support......................................................................................................11
2.2 Connectors .................................................................................................................12
2.2.1 Back Panel Connectors................................................................................13
2.2.2 Internal I/O Connectors ................................................................................14
2.2.3 External I/O Connectors ...............................................................................21
2.3 Jumper Blocks............................................................................................................24
2.3.1 Front Panel Audio Connector/Jumper Block.................................................24
2.3.2 BIOS Setup Configuration Jumper Block......................................................25
2.4 I/O Shield....................................................................................................................26
2.5 Mechanical Considerations.........................................................................................27
2.6 Electrical Considerations ............................................................................................28
2.6.1 Power Consumption.....................................................................................28
2.6.2 Add-in Board Considerations........................................................................28
2.6.3 Standby Current Requirements ....................................................................29
2.6.4 Fan Connector Current Capability ................................................................30
2.6.5 Power Supply Considerations ......................................................................30
2.6.6 Standby Power Indicator LED ......................................................................31
2.7 Reliability ....................................................................................................................32
2.8 Thermal Considerations..............................................................................................32
2.8.1 High Temperature Zones .............................................................................32
2.8.2 Thermal Monitoring ......................................................................................34
3Regulatory Compliance Information
3.1 Regulatory Compliance ..............................................................................................35
3.1.1 Safety Regulations .......................................................................................35
3.1.2 EMC Regulations .........................................................................................35
3.1.3 Product Certification Markings (Board Level) ...............................................36
Figures
1. Desktop Board D845GBV Components......................................................................10
2. Back Panel Connectors ..............................................................................................13
3. Audio, Power, and Hardware Control Connectors ......................................................15
4. Add-in Board and Peripheral Interface Connectors.....................................................19
5. External I/O Connectors .............................................................................................21
6. Location of the Jumper Blocks....................................................................................24
7. I/O Shield Dimensions ................................................................................................26

Product Supplement Document for the Intel Desktop Board D845GBV
vi
8. Desktop Board Dimensions ........................................................................................27
9. Location of the Standby Power Indicator LED ............................................................31
10. Localized High Temperature Zones............................................................................33
11. Thermal Monitoring.....................................................................................................34
Tables
1. Feature Summary........................................................................................................ 7
2. Cross Reference of Footnotes from the Technical Product Specification..................... 9
3. Supported Processors ................................................................................................11
4. Front Panel Audio Connector .....................................................................................16
5. Auxiliary Line In Connector.........................................................................................16
6. Rear Chassis Fan Connector .....................................................................................16
7. ATAPI CD-ROM Connector ........................................................................................16
8. ATX12V Power Connector..........................................................................................17
9. Processor Fan Connector...........................................................................................17
10. Main Power Connector ...............................................................................................18
11. Chassis Intrusion Connector.......................................................................................18
12. Front Chassis Fan Connector.....................................................................................18
13. SCSI LED Connector..................................................................................................20
14. Front Panel USB Connector .......................................................................................21
15. Front Panel Connector ...............................................................................................22
16. States for a One-Color Power LED.............................................................................23
17. States for a Two-Color Power LED.............................................................................23
18. Auxiliary Front Panel Power/Sleep/Message-Waiting LED Connector ........................23
19. Front Panel Audio Connector/Jumper Block ...............................................................25
20. BIOS Setup Configuration Jumper Settings................................................................25
21. Power Usage..............................................................................................................28
22. Standby Current Requirements ..................................................................................29
23. Fan Connector Current Capability ..............................................................................30
24. Thermal Considerations for Components ...................................................................33
25. Safety Regulations .....................................................................................................35
26. EMC Regulations........................................................................................................35

7
1 Overview
1.1 Feature Summary
Table 1 summarizes the major features of the Intel®Desktop Board D845GBV.
Table 1. Feature Summary
Form Factor ATX (12.00 inches by 8.20 inches)
Processor • Support for an Intel®Pentium®4 processor in a µPGA478 socket with a
400/533 MHz system bus
• Support for an Intel®Celeron®processor in a µPGA478 socket with a 400 MHz
system bus
Memory • Two 184-pin Double Data Rate (DDR) SDRAM Dual Inline Memory Module
(DIMM) sockets
• Support for single-sided or double-sided DIMMs (DDR 200 and DDR 266)
• Support for up to 2 GB system memory
NOTE: Desktop Boards using the Intel®845G Chipset Desktop Board have
been designed to support DIMMs based on 512 Mbit technology for a
maximum onboard capacity of up to 2 GB, but this technology has not
been validated. Please refer to the following Intel web site for the latest
list of tested memory:
http://developer.intel.com/design/motherbd/bv/bv_mem.htm
Chipset Intel®845G Chipset, consisting of:
• Intel®82845G Graphics and Memory Controller Hub (GMCH)
• Intel®82801DB I/O Controller Hub (ICH4)
• 4 Mbit Firmware Hub (FWH)
Audio Audio subsystem for AC ‘97 processing using the Analog Devices AD1981A codec
Video • Intel®Extreme Graphics controller
• AGP connector supporting 1x, 2x, and 4x AGP cards (1.5 V only) or an AGP
Digital Display (ADD) card
• Integrated retention mechanism
I/O Control LPC Bus I/O controller (SMSC LPC47M172 or National Semiconductor PC87372)
Peripheral
Interfaces
• Up to six USB ports
• One serial port
• One parallel port
• Two IDE interfaces with UDMA 33, ATA-66/100 support
• One diskette drive interface
• PS/2†keyboard and mouse ports
• Three fan connectors
Expansion
Capabilities
Six PCI bus add-in card connectors (SMBus routed to PCI bus connector 2)
continued

Product Supplement Document for the Intel Desktop Board D845GBV
8
Table 1. Feature Summary (continued)
Hardware Monitor
Subsystem
• Voltage sense to detect out of range power supply voltages
• Thermal sense to detect out of range thermal values
• Two fan sense inputs used to monitor fan activity
• Fan speed control
• Hardware management ASIC
BIOS • Intel/AMI BIOS (resident in the 4 Mbit FWH)
• Support for Advanced Configuration and Power Interface (ACPI), Plug and Play,
and SMBIOS
Instantly Available
PC Technology
• Support for PCI Local Bus Specification Revision 2.2
• Suspend to RAM support
• Wake on PCI, CNR, RS-232, front panel, PS/2 devices, and USB ports
CNR One Communication and Networking Riser (CNR) connector (slot shared with
PCI bus connector 6)
LAN Intel®82562ET 10/100 Mbit/sec Platform LAN Connect (PLC) device
✏ NOTE
The LAN subsystem and the CNR connector are mutually exclusive features.
1.2 Online Support
To find information about…Visit this World Wide Web site:
The Intel Desktop Board D845GBV under
“Product Info”or “Customer Support”
http://www.intel.com/design/motherbd
http://support.intel.com/support/motherboards/desktop
Available configurations for the Intel
Desktop Board D845GBV
http://developer.intel.com/design/motherbd/bv/bv_available.htm

Overview
9
1.3 Footnote Cross Reference
This document is a companion document to the Technical Product Specification for Intel Desktop
Boards using the Intel 845G Chipset. The Technical Product Specification (order number:
A81229-001) contains footnotes that refer you to this document for information specific to this
Desktop Board. Table 2 lists all of the footnotes in the Technical Product Specification that refer
to this document.
Table 2. Cross Reference of Footnotes from the Technical Product Specification
Footnote
Number Footnote Text Cross Reference
1 Form factors are product-dependent. The Desktop Board D845GBV uses the ATX
form-factor. See Section 2.5 on page 27 for
more information on the form factor.
2 Memory support (DDR SDRAM or SDR
SDRAM) is product-dependent.
The Desktop Board D845GBV supports DDR
SDRAM.
6 Some Desktop Boards may use a different BIOS
core.
The D845GBV Desktop Board uses an Intel/AMI
BIOS core.
7 Memory support (DDR SDRAM or SDR
SDRAM) is product-dependent.
The Desktop Board D845GBV supports DDR
SDRAM.
8 Memory support (DDR SDRAM or SDR
SDRAM) is product-dependent.
The Desktop Board D845GBV supports DDR
SDRAM.
9 Processor support is product-dependent. Supported processors are listed in Section 2.1
on page 11.
10 Memory support (DDR SDRAM or SDR
SDRAM) is product-dependent.
The Desktop Board D845GBV supports DDR
SDRAM.
12 The front panel audio connector can also be
used as a jumper block for routing audio signals.
Figure 3 on page 15 shows the location of the
front panel audio connector.
Table 4 on page 16 lists the signal names when
this connector is used as a front panel audio
connector.
Section 2.3.1 on page 24 describes the jumper
settings when this connector is used as a
jumper block.
17 Standby current requirements are product
dependent.
Power usage and standby current requirements
are described in Section 2.6.3 on page 29.
19 Standby current requirements are product
dependent.
Power usage and standby current requirements
are described in Section 2.6.3 on page 29.
20 Standby current requirements are product
dependent.
Power usage and standby current requirements
are described in Section 2.6.3 on page 29.
21 The location of the standby power indicator LED
is product dependent.
Figure 9 on page 31 shows the location of the
standby power indicator LED.
22 Some Desktop Boards may use a different BIOS
core.
The Desktop Board D845GBV uses an Intel/AMI
BIOS core.

Product Supplement Document for the Intel Desktop Board D845GBV
10
1.4 Board Layout
Figure 1 shows the location of the major components on the Desktop Board D845GBV.
F
PQRSTU O LNM
A B C D E
H
K
I
J
G
CC
BB
OM13576
X
Y
Z
AA
W
V
A Audio codec P Speaker
B Front panel audio connector Q Battery
C Auxiliary line-in connector R SCSI LED connector
D Rear chassis fan connector S Chassis intrusion connector
E ATAPI CD-ROM connector T Front chassis fan connector
F Back panel connectors U BIOS Setup configuration jumper block
G +12V power connector (ATX12V) V Auxiliary front panel power LED connector
H µPGA478 processor socket W 4 Mbit Firmware Hub (FWH)
I Processor fan connector X Front panel connector
J Intel 82845G Graphics and
Memory Controller Hub (GMCH)
Y Intel 82801DB I/O Controller Hub (ICH4)
K DIMM sockets Z Front panel USB connector
L I/O Controller AA AGP connector
M Power connector BB PCI bus add-in card connectors
N Diskette drive connector CC CNR connector (optional)
O IDE connectors
Figure 1. Desktop Board D845GBV Components

11
2 Product-Specific Features
2.1 Processor Support
CAUTION
Use only the processors listed below. Use of unsupported processors can damage the Desktop
Board, the processor, and the power supply. See the Specification Update for Intel®Desktop
Boards using the Intel 845G Chipset for the most up-to-date list of supported processors for these
boards.
The Desktop Boards provide a µPGA478 processor socket. Table 3 lists the supported processors.
All supported onboard memory can be cached. See the processor’s data sheet for cachability
limits.
Table 3. Supported Processors
Type/Package Designation System Bus L2 Cache Size
Celeron processor 1.7, 1.8, and 1.9 GHz 400 MHz 128 KB
Pentium 4 processor 1.4, 1.5, 1.6, 1.7, 1.8,
1.9, and 2.0 GHz
400 MHz 256 KB
Pentium 4 processor 1.6A, 1.8A, 2.0A, 2.2,
and 2.4 GHz
400 MHz 512 KB
Pentium 4 processor 2.26 and 2.4B GHz 533 MHz 512 KB
# INTEGRATOR’S NOTES
• Use only ATX12V-compliant power supplies with this Desktop Board. ATX12V power
supplies have an additional power lead that provides required supplemental power for the
processor. Always connect the 20-pin and 4-pin leads of ATX12V power supplies to the
corresponding connectors on the Desktop Board, otherwise the Desktop Board will not
boot.
• Do not use a standard ATX power supply. The Desktop Board will not boot with a
standard ATX power supply.

Product Supplement Document for the Intel Desktop Board D845GBV
12
2.2 Connectors
CAUTION
Only the back panel USB, front panel USB, VGA, and PS/2 connectors have overcurrent
protection. The Desktop Boards’internal connectors are not overcurrent protected and should
connect only to devices inside the computer’s chassis, such as fans and internal peripherals. Do
not use these connectors to power devices external to the computer’s chassis. A fault in the load
presented by the external devices could cause damage to the computer, the interconnecting cable,
and the external devices themselves.
This section describes the Desktop Board’s connectors. The connectors can be divided into the
following groups:
• Back panel I/O connectors (see page 13)
 PS/2 keyboard and mouse
 USB
 Parallel port
 Serial port
 VGA
 LAN (optional)
 Audio (line out, line in, and mic in)
• Internal I/O connectors (see page 14)
 Audio (auxiliary line input and ATAPI CD-ROM, and front panel audio)
 Fans
 Power
 Add-in boards (PCI and AGP)
 CNR (optional)
 IDE
 Diskette drive
 SCSI LED
 Chassis intrusion
• External I/O connectors (see page 21)
 Front panel USB
 Front panel (power/sleep/message-waiting LED, power switch, hard drive activity LED,
reset switch, and auxiliary front panel power LED)
 Auxiliary front panel power/sleep/message-waiting LED

Product-Specific Features
13
2.2.1 Back Panel Connectors
Figure 2 shows the location of the back panel connectors. The back panel connectors are
color-coded in compliance with PC 99 recommendations. The figure legend below lists the
colors used.
OM13577
B
A
J K
G
F
C
MLE
I
DH
Item Description Color
A PS/2 mouse port Green
B PS/2 keyboard port Purple
C USB port (optional) Black
D USB port (optional) Black
E Serial port A Teal
F Parallel port Burgundy
G VGA Dark blue
H USB port Black
I LAN (optional) Black
J USB port Black
K Mic in Pink
L Audio line out Lime green
M Audio line in Light blue
Figure 2. Back Panel Connectors

Product Supplement Document for the Intel Desktop Board D845GBV
14
# INTEGRATOR’S NOTE
The back panel audio line out connector is designed to power headphones or amplified speakers
only. Poor audio quality occurs if passive (non-amplified) speakers are connected to this output.
2.2.2 Internal I/O Connectors
The internal I/O connectors are divided into the following functional groups:
• Audio, power, and hardware control (see page 15)
 Auxiliary line in
 ATAPI CD-ROM
 Front panel audio
 Fans
 ATX12V power
 Main power
• Add-in boards and peripheral interfaces (see page 19)
 CNR (optional)
 PCI bus
 AGP
 IDE
 Diskette drive
 SCSI LED
2.2.2.1 Expansion Slots
The Desktop Board has the following expansion slots:
• One AGP connector. The AGP connector is keyed for 1.5 V AGP cards only. Do not install a
legacy 3.3 V AGP card. The AGP connector is not mechanically compatible with legacy
3.3 V AGP cards.
• Three PCI rev 2.2 compliant local bus slots. The SMBus is routed to PCI bus connector 2.
• One CNR (optional), shared with PCI bus connector 3 (ATX expansion slot 1).
# INTEGRATOR’S NOTE
This document references back-panel slot numbering with respect to processor location on the
Desktop Board. The AGP slot is not numbered. PCI slots are identified as PCI slot #x, starting
with the slot closest to the processor. The CNR slot shares an ATX expansion slot 3. The
ATX/MicroATX specifications identify expansion slot locations with respect to the far edge of a
full-sized ATX chassis. The ATX specification and the Desktop Board’s silkscreen are opposite
and could cause confusion. The ATX numbering convention is made without respect to slot type
(PCI vs. AGP), but refers to an actual slot location on a chassis. Figure 4 on page 19 illustrates
the Desktop Board’s PCI slot numbering.

Product-Specific Features
15
2.2.2.2 Audio, Power, and Hardware Control Connectors
Figure 3 shows the location of the audio, power, and hardware control connectors.
OM13578
910
2
1
4
1
4
1
1
13
1
3
4
21
3
1
3
10
20 11
1
AB DC E
F
G
H
I
Item Description For more information see:
A Front panel audio Table 4
B Auxiliary line in, ATAPI style (white) Table 5
C Rear chassis fan Table 6
D ATAPI CD-ROM (black) Table 7
E +12 V power connector (ATX12V) Table 8
F Processor fan Table 9
G Main power Table 10
H Chassis intrusion Table 11
I Front chassis fan Table 12
Figure 3. Audio, Power, and Hardware Control Connectors

Product Supplement Document for the Intel Desktop Board D845GBV
16
Table 4. Front Panel Audio Connector
Pin Signal Name Pin Signal Name
1 MIC_IN 2 Ground
3 MIC_BIAS 4 +5 V
5 RIGHT_OUT 6 RIGHT_IN
7 Ground 8 Key
9 LEFT_OUT 10 LEFT_IN
# INTEGRATOR’S NOTE
The front panel audio connector is alternately used as a jumper block for routing audio signals.
Refer to Section 2.3.1 on page 24 for more information.
Table 5. Auxiliary Line In Connector
Pin Signal Name
1 Left auxiliary line in
2 Ground
3 Ground
4 Right auxiliary line in
Table 6. Rear Chassis Fan Connector
Pin Signal Name
1 (Note)
2 +12 V
3 REAR_TACH_OUT
Note: Pin 1 is Control if the Desktop Board uses the hardware monitoring and fan control ASIC.
Pin 1 is Ground if the Desktop Board uses the hardware monitoring ASIC.
Table 7. ATAPI CD-ROM Connector
Pin Signal Name
1 Left audio input from CD-ROM
2 CD audio differential ground
3 CD audio differential ground
4 Right audio input from CD-ROM

Product-Specific Features
17
# INTEGRATOR’S NOTES
• Use only ATX12V-compliant power supplies with the Desktop Board D845GBV. ATX12V
power supplies have an additional power lead that provides required supplemental power
for the processor. Always connect the 20-pin and 4-pin leads of ATX12V power supplies
to the corresponding connectors on the Desktop Board, otherwise the Desktop Board will
not boot.
• Do not use a standard ATX power supply. The Desktop Board will not boot with a
standard ATX power supply.
Table 8. ATX12V Power Connector
Pin Signal Name Pin Signal Name
1 Ground 2 Ground
3 +12 V 4 +12 V
Table 9. Processor Fan Connector
Pin Signal Name
1 (Note)
2 +12 V
3 CPU_FAN_TACH
Note: Pin 1 is Control if the Desktop Board uses the hardware monitoring and fan control ASIC.
Pin 1 is Ground if the Desktop Board uses the hardware monitoring ASIC.

Product Supplement Document for the Intel Desktop Board D845GBV
18
Table 10. Main Power Connector
Pin Signal Name Pin Signal Name
1 +3.3 V 11 +3.3 V
2 +3.3 V 12 -12 V
3 Ground 13 Ground
4 +5 V 14 PS-ON# (power supply remote on/off)
5 Ground 15 Ground
6 +5 V 16 Ground
7 Ground 17 Ground
8 PWRGD (Power Good) 18 No connect
9 +5 V (Standby) 19 +5 V
10 +12 V 20 +5 V
Table 11. Chassis Intrusion Connector
Pin Signal Name
1 Intruder
2 Ground
Table 12. Front Chassis Fan Connector
Pin Signal Name
1 (Note 1)
2 +12 V
3 (Note 2)
Notes: 1. Pin 1 is Control if the Desktop Board uses the hardware monitoring and fan control ASIC.
Pin 1 is Ground if the Desktop Board uses the hardware monitoring ASIC.
2. Pin 3 is FRONT_TACH_OUT if the Desktop Board uses the hardware monitoring and fan control ASIC.
Pin 3 is No connect if the Desktop Board uses the hardware monitoring ASIC.

Product-Specific Features
19
2.2.2.3 Add-in Board and Peripheral Interface Connectors
Figure 4 shows the location of the add-in board connector and peripheral connectors for the
Desktop Board D845GBV. Note the following considerations for the PCI bus connectors:
• All of the PCI bus connectors are bus master capable.
• SMBus signals are routed to PCI bus connector 2. This enables PCI bus add-in boards with
SMBus support to access sensor data on the Desktop Board. The specific SMBus signals are
as follows:
 The SMBus clock line is connected to pin A40.
 The SMBus data line is connected to pin A41.
OM13579
1
240
39
1
2
33
34
1
1
240
39
KI
JL
A B C D E FG H
Item Description
A CNR (optional)
B PCI bus connector 6
C PCI bus connector 5
D PCI bus connector 4
E PCI bus connector 3
F PCI bus connector 2
G PCI bus connector 1
H AGP connector
I Diskette drive
J Primary IDE
K Secondary IDE
L SCSI LED
Figure 4. Add-in Board and Peripheral Interface Connectors

Product Supplement Document for the Intel Desktop Board D845GBV
20
# INTEGRATOR’S NOTE
The AGP connector is keyed for 1.5 V AGP cards only. Do not attempt to install a legacy
3.3 V AGP card. The AGP connector is not mechanically compatible with legacy 3.3 V AGP
cards.
Table 13. SCSI LED Connector
Pin Signal Name
1 SCSI_ACT#
2 No connect
# INTEGRATOR’S NOTE
Not all PCI video cards can be used in PCI bus connectors 1 and 2 (the PCI bus connectors closest
to the processor). To avoid clearance problems, install PCI video cards in PCI bus connector 3.