Intel BLKDH61WWB3 Configuration guide

Intel® Desktop Board
DH61WW
Technical Product Specification
March 2012
Part Number: G23564-003
The Intel®Desktop Board DH61WW 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 Intel Desktop Board DH61WW Specification Update.

ii
Revision History
Revision Revision History Date
-001 First release of the Intel®Desktop Board DH61WW Technical Product
Specification
February 2011
-002 Second release of the Intel®Desktop Board DH61WW Technical Product
Specification
May 2011
-003 Updated maximum memory supported from 8 GB to 16 GB March 2012
Disclaimer
This product specification applies to only the standard Intel®Desktop Board DH61WW with BIOS
identifier BEH6110H.86A.
INFORMATION IN THIS DOCUMENT IS PROVIDED IN CONNECTION WITH INTEL®PRODUCTS. NO LICENSE,
EXPRESS OR IMPLIED, BY ESTOPPEL OR OTHERWISE, TO ANY INTELLECTUAL PROPERTY RIGHTS IS
GRANTED BY THIS DOCUMENT. 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 PROPERTY RIGHT. UNLESS OTHERWISE AGREED IN
WRITING BY INTEL, THE INTEL PRODUCTS ARE NOT DESIGNED NOR INTENDED FOR ANY APPLICATION IN
WHICH THE FAILURE OF THE INTEL PRODUCT COULD CREATE A SITUATION WHERE PERSONAL INJURY OR
DEATH MAY OCCUR.
All Intel®desktop boards are evaluated as Information Technology Equipment (I.T.E.) for use in personal
computers (PC) for installation in homes, offices, schools, computer rooms, and similar locations. The
suitability of this product for other PC or embedded non-PC applications or other environments, such as
medical, industrial, alarm systems, test equipment, etc. may not be supported without further evaluation by
Intel.
Intel Corporation may have patents or pending patent applications, trademarks, copyrights, or other
intellectual property 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 may make changes to specifications and product descriptions at any time, without notice.
Designers must not rely on the absence or characteristics of any features or instructions marked “reserved”
or “undefined.” Intel reserves these for future definition and shall have no responsibility whatsoever for
conflicts or incompatibilities arising from future changes to them.
Intel desktop boards may contain design defects or errors known as errata, which 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.
Intel, Intel Core, and Pentium are trademarks of Intel Corporation in the U.S. and/or other countries.
* Other names and brands may be claimed as the property of others.
Copyright ©2011, 2012, Intel Corporation. All rights reserved.

iii
Board Identification Information
Basic Desktop Board DH61WW Identification Information
AA Revision BIOS Revision Notes
G23116-202 BEH6110H.86A.0016 1,2
G23116-203 BEH6110H.86A.0016 1,2
Notes:
1. The AA number is found on a small label on the component side of the board.
2. The H61 processor used on this AA revision consists of the following component:
Device Stepping S-Spec Numbers
82H61 B3 SLJ4B
Specification Changes or Clarifications
The table below indicates the Specification Changes or Specification Clarifications that
apply to the Intel®Desktop Board DH61WW.
Specification Changes or Clarifications
Date Type of Change Description of Change or Clarification
May 2011 Spec Clarifications •The Intel H61 Express Chipset does not support RAID.
The following sections of this manual have been updated:
―Reference to RAID in Table 1. Feature Summary has
been deleted
―Section 1.9.1.1 Serial ATA RAID has been deleted
―Section 1.9.1.2 Intel®Rapid Recover Technology has
been deleted
―The Caution in Section 3.1 Introduction has been
deleted
•The maximum memory supported changed from 16 GB to
8 GB in the following sections of this manual:
―Table 1. Feature Summary
―Section 1.6 System Memory
―Section 2.1.1 Addressable Memory
―Figure 8. Detailed System Memory Address Map
―Table 9. System Memory Map
•The Korean Certification mark has changed. The following
sections of this manual have been updated:
―Section 5.1.4 EMC Regulations. The Korean Class B
Statement translation has been updated.
―Section 5.1.6 Regulatory Compliance Marks (Board
Level). The new Korean Certification mark has been
added.
March 2012 Spec Clarification Updated maximum memory supported from 8 GB to 16 GB

iv
Errata
Current characterized errata, if any, are documented in a separate Specification
Update. See http://developer.intel.com/products/desktop/motherboard/index.htm
for the latest documentation.

v
Preface
This Technical Product Specification (TPS) specifies the board layout, components,
connectors, power and environmental requirements, and the BIOS for the
Intel®Desktop Board DH61WW.
Intended Audience
The TPS is intended to provide detailed, technical information about the Intel Desktop
Board DH61WW 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
Chapter Description
1 A description of the hardware used on the Intel Desktop Board DH61WW
2 A map of the resources of the Intel Desktop Board
3 The features supported by the BIOS Setup program
4 A description of the BIOS error messages, beep codes, and POST codes
5 Regulatory compliance and battery disposal information
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.
CAUTION
Cautions are included to help you avoid damaging hardware or losing data.

Intel Desktop Board DH61WW Technical Product Specification
vi
Other Common Notation
# Used after a signal name to identify an active-low signal (such as USBP0#)
GB Gigabyte (1,073,741,824 bytes)
GB/s Gigabytes per second
Gb/s Gigabits per second
KB Kilobyte (1024 bytes)
Kbit Kilobit (1024 bits)
kbits/s 1000 bits per second
MB Megabyte (1,048,576 bytes)
MB/s Megabytes per second
Mbit Megabit (1,048,576 bits)
Mbits/s 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.

vii
Contents
Revision History
Disclaimer............................................................................................... ii
Board Identification Information .................................................................iii
Specification Changes or Clarifications.........................................................iii
Errata.................................................................................................... iv
Preface
Intended Audience ................................................................................... v
What This Document Contains.................................................................... v
Typographical Conventions ........................................................................ v
1Product Description
1.1Overview........................................................................................ 11
1.1.1Feature Summary ................................................................ 11
1.1.2Board Layout ....................................................................... 13
1.1.3Block Diagram ..................................................................... 15
1.2Legacy Considerations...................................................................... 16
1.3Online Support................................................................................ 16
1.4Processor ....................................................................................... 16
1.5Intel®H61 Express Chipset ............................................................... 17
1.6System Memory .............................................................................. 17
1.6.1Memory Configurations ......................................................... 18
1.7Graphics Subsystem ........................................................................ 20
1.7.1Integrated Graphics.............................................................. 20
1.7.2PCI Express x16 Graphics ...................................................... 20
1.8USB............................................................................................... 21
1.9SATA Interfaces .............................................................................. 21
1.10Legacy I/O Controller....................................................................... 22
1.10.1Serial Port ........................................................................... 22
1.11Audio Subsystem............................................................................. 23
1.11.1Audio Subsystem Software .................................................... 24
1.11.2Audio Headers and Connectors ............................................... 24
1.12LAN Subsystem............................................................................... 26
1.12.1Intel®82579V Gigabit Ethernet Controller................................ 26
1.12.2LAN Subsystem Software....................................................... 26
1.12.3RJ-45 LAN Connector with Integrated LEDs .............................. 27
1.13Real-Time Clock Subsystem .............................................................. 28
1.14Thermal Monitoring.......................................................................... 29
1.15Platform Management and Security
.................................................... 30
1.15.1Hardware Management Subsystem ......................................... 30
1.15.2Hardware Monitoring............................................................. 30

Intel Desktop Board DH61WW Technical Product Specification
viii
1.16Power Management ......................................................................... 31
1.16.1ACPI................................................................................... 31
1.16.2Hardware Support ................................................................ 34
2Technical Reference
2.1Memory Resources .......................................................................... 38
2.1.1Addressable Memory............................................................. 38
2.1.2Memory Map........................................................................ 40
2.2Connectors and Headers................................................................... 40
2.2.1Back Panel Connectors
.......................................................... 41
2.2.2Component-side Connectors and Headers ................................ 42
2.3BIOS Configuration Jumper Block....................................................... 51
2.4Mechanical Considerations ................................................................ 53
2.4.1Form Factor......................................................................... 53
2.5Electrical Considerations
................................................................... 54
2.5.1Power Supply Considerations ................................................. 54
2.5.2Fan Header Current Capability................................................ 55
2.5.3Add-in Board Considerations .................................................. 55
2.6Thermal Considerations
.................................................................... 56
2.7Reliability ....................................................................................... 58
2.8Environmental ................................................................................ 58
3Overview of BIOS Features
3.1Introduction ................................................................................... 59
3.2System Management BIOS (SMBIOS)................................................. 61
3.3Legacy USB Support ........................................................................ 61
3.4BIOS Updates ................................................................................. 62
3.4.1Language Support ................................................................ 62
3.4.2Custom Splash Screen .......................................................... 63
3.5BIOS Recovery................................................................................ 63
3.6Boot Options................................................................................... 64
3.6.1Optical Drive Boot ................................................................ 64
3.6.2Network Boot....................................................................... 64
3.6.3Booting Without Attached Devices........................................... 64
3.6.4Changing the Default Boot Device During POST ........................ 64
4Error Messages and Beep Codes
4.1Speaker ......................................................................................... 65
4.2BIOS Beep Codes ............................................................................ 65
4.3Front-panel Power LED Blink Codes
.................................................... 66
4.4BIOS Error Messages ....................................................................... 66
4.5Port 80h POST Codes ....................................................................... 67
5Regulatory Compliance and Battery Disposal Information
5.1Regulatory Compliance..................................................................... 73
5.1.1Safety Standards.................................................................. 73
5.1.2European Union Declaration of Conformity Statement
................ 74
5.1.3Product Ecology Statements................................................... 75

Contents
ix
5.1.4EMC Regulations .................................................................. 77
5.1.5ENERGY STAR* 5.0, e-Standby, and ErP Compliance ................. 80
5.1.6Regulatory Compliance Marks (Board Level)
............................. 81
5.2Battery Disposal Information............................................................. 82
Figures
1. Major Board Components.................................................................. 13
2. Block Diagram ................................................................................ 15
3. Memory Channel and DIMM Configuration ........................................... 19
4. Back Panel Audio Connector Options .................................................. 25
5. LAN Connector LED Locations............................................................ 27
6. Thermal Sensors and Fan Headers ..................................................... 29
7. Location of the Standby Power LED (Green) ........................................ 37
8. Detailed System Memory Address Map ............................................... 39
9. Back Panel Connectors ..................................................................... 41
10. Component-side Connectors and Headers ........................................... 42
11. Connection Diagram for Front Panel Header ........................................ 48
12. Connection Diagram for Front Panel USB Headers ................................ 50
13. Location of the Jumper Block............................................................. 51
14. Board Dimensions ........................................................................... 53
15. Localized High Temperature Zones..................................................... 57
Tables
1. Feature Summary............................................................................ 11
2. Components Shown in Figure 1 ......................................................... 14
3. Supported Memory Configurations ..................................................... 18
4. Audio Jack Support.......................................................................... 23
5. LAN Connector LED States ................................................................ 27
6. Effects of Pressing the Power Switch .................................................. 31
7. Power States and Targeted System Power........................................... 32
8. Wake-up Devices and Events ............................................................ 33
9. System Memory Map ....................................................................... 40
10. Component-side Connectors and Headers Shown in Figure 10................ 43
11. TPM Header.................................................................................... 44
12. Serial Port Header ........................................................................... 44
13. S/PDIF Header ................................................................................ 44
14. Front Panel Audio Header for Intel HD Audio........................................ 45
15. Front Panel Audio Header for AC ’97 Audio .......................................... 45
16. Front Panel USB Header ................................................................... 45
17. SATA Connectors............................................................................. 45
18. Chassis Intrusion Header.................................................................. 46
19. Fan Headers ................................................................................... 46
20. Processor Core Power Connector........................................................ 47
21. Main Power Connector...................................................................... 47
22. Front Panel Header .......................................................................... 48

Intel Desktop Board DH61WW Technical Product Specification
x
23. States for a One-Color Power LED...................................................... 49
24. LPC Debug Header........................................................................... 50
25. BIOS Setup Configuration Jumper Settings.......................................... 52
26. Recommended Power Supply Current Values ....................................... 54
27. Fan Header Current Capability........................................................... 55
28. Thermal Considerations for Components ............................................. 57
29. Environmental Specifications............................................................. 58
30. BIOS Setup Program Menu Bar.......................................................... 60
31. BIOS Setup Program Function Keys.................................................... 60
32. Acceptable Drives/Media Types for BIOS Recovery ............................... 63
33. Boot Device Menu Options ................................................................ 64
34. BIOS Beep Codes ............................................................................ 65
35. Front-panel Power LED Blink Codes.................................................... 66
36. BIOS Error Messages ....................................................................... 66
37. Port 80h POST Code Ranges.............................................................. 67
38. Port 80h POST Codes ....................................................................... 68
39. Typical Port 80h POST Sequence........................................................ 72
40. Safety Standards............................................................................. 73
41. EMC Regulations ............................................................................. 77
42. Regulatory Compliance Marks............................................................ 81

11
1Product Description
1.1 Overview
1.1.1 Feature Summary
Table 1 summarizes the major features of the board.
Table 1. Feature Summary
Form Factor MicroATX (9.60 inches by 7.80 inches [243.84 millimeters by
198.12 millimeters])
Processor •Intel®Core™ i7, Intel®Core™ i5, Intel®Core™ i3, and Intel®Pentium®
processors in an LGA1155 socket with up to 95 W TDP:
―Integrated graphics processing (processors with Intel®Graphics
Technology)
―External graphics interface controller
―Integrated memory controller
Chipset Intel®H61 Express Chipset consisting of the Intel®H61 Platform Controller
Hub (PCH)
Memory •Two 240-pin DDR3 SDRAM Dual Inline Memory Module (DIMM) sockets
•Support for DDR3 1333 MHz and DDR3 1066 MHz DIMMs
•Support for 1 Gb, 2 Gb, and 4 Gb memory technology
•Support for up to 16 GB of system memory with two DIMMs using 4 Gb
memory technology
•Support for non-ECC memory
Graphics •Integrated graphics support for processors with Intel®Graphics Technology
•Discrete graphics support for PCI Express 2.0 x16 add-in graphics card
Audio •Intel®High Definition Audio:
―Realtek* ALC892 audio codec
―S/PDIF audio header
―Front panel audio header
continued

Intel Desktop Board DH61WW Technical Product Specification
12
Table 1. Feature Summary (continued)
Peripheral
Interfaces
•Six USB ports:
―Four USB 2.0 ports are implemented with stacked back panel connectors
―Two USB 2.0 front panel ports are implemented through one dual-port
internal header
•Four SATA interfaces through the Intel H61 Express Chipset
•One serial port header
•One parallel port connector on the back panel
•One PS/2* keyboard/mouse port on back panel
Legacy I/O Control •Nuvoton* W83677HG-i Super I/O controller for hardware management and
serial port, parallel port, and PS/2 support
BIOS •Intel®BIOS resident in the SPI Flash device
•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
•Support for PCI Express*
•Suspend to RAM support
•Wake on Conventional PCI, PCI Express, LAN, front panel, serial, PS/2, and
USB ports
LAN Support Gigabit (10/100/1000 Mbits/s) LAN subsystem using the Intel®82579V Gigabit
Ethernet Controller
Expansion
Capabilities
•One PCI Express 2.0 x16 add-in card connector
•One PCI Express 2.0 x1 add-in card connector
•One Conventional PCI bus connector
Hardware Monitor
Subsystem
•Hardware monitoring through the Nuvoton Super I/O controller
•Voltage sense to detect out of range power supply voltages
•Thermal sense to detect out of range thermal values
•Two fan headers
•Two fan sense inputs used to monitor fan activity
•Fan speed control

Product Description
13
1.1.2 Board Layout
Figure 1 shows the location of the major components on Intel Desktop Board
DH61WW.
Figure 1. Major Board Components
Table 2 lists the components identified in Figure 1.

Intel Desktop Board DH61WW Technical Product Specification
14
Table 2. Components Shown in Figure 1
Item/callout
from Figure 1 Description
A Conventional PCI bus add-in card connector
B Chassis intrusion header
C S/PDIF header
D PCI Express x1 add-in card connector
E Battery
F PCI Express x16 add-in card connector
G Back panel connectors
H Standby power LED
I 12 V internal power connector (ATX12V)
J Rear chassis fan header
K Piezoelectric speaker
L LGA1155 processor socket
M Processor fan header
N Low Pin Count (LPC) Debug header
O DIMM 1 (Channel A DIMM 1)
P DIMM 2 (Channel B DIMM 1)
Q Trusted Platform Module (TPM) header
R Main power connector (2 x 12)
S SATA connectors
T BIOS setup configuration jumper block
U Front panel header
V Intel H61 Express Chipset
W Serial port header
X Front panel USB 2.0 headers
Y Front panel audio header

Product Description
15
1.1.3 Block Diagram
Figure 2 is a block diagram of the major functional areas of the board.
Figure 2. Block Diagram

Intel Desktop Board DH61WW Technical Product Specification
16
1.2 Legacy Considerations
This board differs from other Intel Desktop Board products, with specific changes
including (but not limited to) the following:
•No Parallel ATA (PATA) IDE drive connector
1.3 Online Support
To find information about… Visit this World Wide Web site:
Intel Desktop Board DH61WW http://www.intel.com/products/motherboard/index.htm
Desktop Board Support http://www.intel.com/p/en_US/support?iid=hdr+support
Available configurations for the Intel
Desktop Board DH61WW
http://ark.intel.com
Supported processors http://processormatch.intel.com
Chipset information http://www.intel.com/products/desktop/chipsets/index.htm
BIOS and driver updates http://downloadcenter.intel.com
Tested memory http://www.intel.com/support/motherboards/desktop/sb/CS-
025414.htm
Integration information http://www.intel.com/support/go/buildit
1.4 Processor
The board is designed to support the Intel Core i7, Intel Core i5, Intel Core i3, and
Intel Pentium processors in an LGA1155 socket.
Other processors may be supported in the future. This board is designed to support
processors with a maximum TDP of 95 W. See the Intel web site listed below for the
most up-to-date list of supported processors.
For information about… Refer to:
Supported processors http://processormatch.intel.com
CAUTION
Use only the processors listed on the web site above. Use of unsupported processors
can damage the board, the processor, and the power supply.
NOTE
This board has specific requirements for providing power to the processor. Refer to
Section 2.5.1 on page 54 for information on power supply requirements for this board.

Product Description
17
1.5 Intel®H61 Express Chipset
The Intel H61 Express Chipset consisting of the Intel H61 Platform Controller Hub
(PCH) provides interfaces to the processor and the USB, SATA, LPC, audio, network,
display, and PCI Express. The PCH is a centralized controller for the board’s I/O paths.
For information about Refer to
The Intel H61 Express chipset http://www.intel.com/products/desktop/chipsets/index.htm
Resources used by the chipset Chapter 2
1.6 System Memory
The board has two DIMM sockets and supports the following memory features:
•Two independent memory channels with interleaved mode support
•Supports 1.2 V – 1.8 V DIMM memory voltage
•Support for non-ECC, unbuffered, single-sided or double-sided DIMMs with x8
organization
•16 GB maximum total system memory (with 4 Gb memory technology). Refer to
Section 2.1.1 on page 38 for information on the total amount of addressable
memory.
•Minimum total system memory: 1 GB using 1 Gb x8 module
•Serial Presence Detect
•DDR3 1333 MHz and DDR3 1066 MHz SDRAM DIMMs
NOTE
To be fully compliant with all applicable DDR SDRAM memory specifications, the board
should be populated with DIMMs that support the Serial Presence Detect (SPD) data
structure. This allows the BIOS to read the SPD data and program the chipset to
accurately configure memory settings for optimum performance. If non-SPD memory
is installed, the BIOS will attempt to correctly configure the memory settings, but
performance and reliability may be impacted or the DIMMs may not function under the
determined frequency.

Intel Desktop Board DH61WW Technical Product Specification
18
Table 3 lists the supported DIMM configurations.
Table 3. Supported Memory Configurations
DIMM
Capacity
Configuration (Note) SDRAM
Density
SDRAM Organization
Front-side/Back-side
Number of SDRAM
Devices
512 MB SS 1 Gbit 64 M x16/empty 4
1024 MB SS 1 Gbit 128 M x8/empty 8
1024 MB SS 2 Gbit 128 M x16/empty 4
2048 MB DS 1 Gbit 128 M x8/128 M x8 16
2048 MB SS 2 Gbit 128 M x16/empty 8
4096 MB DS 2 Gbit 256 M x8/256 M x8 16
4096 MB SS 4 Gbit 512 M x8/empty 8
Note: “DS” refers to double-sided memory modules (containing two rows of SDRAM) and “SS” refers to
single-sided memory modules (containing one row of SDRAM).
For information about… Refer to:
Tested Memory http://support.intel.com/support/motherboards/desktop/sb/CS-
025414.htm
1.6.1 Memory Configurations
The Intel Core i7, Intel Core i5, Intel Core i3, and Intel Pentium processors support the
following types of memory organization:
•Dual channel (Interleaved) mode. This mode offers the highest throughput for
real world applications. Dual channel mode is enabled when the installed memory
capacities of both DIMM channels are equal. Technology and device width can vary
from one channel to the other but the installed memory capacity for each channel
must be equal. If different speed DIMMs are used between channels, the slowest
memory timing will be used.
•Single channel (Asymmetric) mode. This mode is equivalent to single channel
bandwidth operation for real world applications. This mode is used when only a
single DIMM is installed or the memory capacities are unequal. Technology and
device width can vary from one channel to the other. If different speed DIMMs are
used between channels, the slowest memory timing will be used.
For information about… Refer to:
Memory Configuration examples http://www.intel.com/support/motherboards/desktop/sb/cs-
011965.htm

Product Description
19
Figure 3 illustrates the memory channel and DIMM configuration.
Figure 3. Memory Channel and DIMM Configuration

Intel Desktop Board DH61WW Technical Product Specification
20
1.7 Graphics Subsystem
The board supports system graphics through either Intel Graphics Technology or a
PCI Express 2.0 x16 add-in graphics card.
1.7.1 Integrated Graphics
The board supports integrated graphics through the Intel®Flexible Display Interface
(Intel®FDI) for processors with Intel Graphics Technology.
1.7.1.1 Analog Display (VGA)
The VGA port supports analog displays. The maximum supported resolution is 2048 x
1536 (QXGA) at a 75 Hz refresh rate. The VGA port is enabled for POST whenever a
monitor is attached, regardless of the DVI-D connector status.
1.7.2 PCI Express x16 Graphics
The Intel Core i7, Intel Core i5, Intel Core i3, and Intel Pentium processors in an
LGA1155 socket support discrete add in graphics cards through the PCI Express 2.0
x16 graphics connector:
•Supports PCI Express GEN2 frequency of 2.5 GHz resulting in 5.0 Gb/s each
direction (500 MB/s) per lane. Maximum theoretical bandwidth on interface is
8 GB/s in each direction, simultaneously, when operating in x16 mode.
•Supports PCI Express GEN1 frequency of 1.25 GHz resulting in 2.5 Gb/s each
direction (250 MB/s) per lane. Maximum theoretical bandwidth on interface is
4 GB/s in each direction, simultaneously, when operating in x16 mode.
For information about Refer to
PCI Express technology http://www.pcisig.com