Asus P5QL-EM - Motherboard - Micro ATX User manual

Motherboard
P5QL-EM

ii
E4403
Third Edition V3
December 2008
Copyright © 2008 ASUSTeK Computer, Inc. All Rights Reserved.
No part of this manual, including the products and software described in it, may be reproduced,
transmitted, transcribed, stored in a retrieval system, or translated into any language in any form or by any
means, except documentation kept by the purchaser for backup purposes, without the express written
permission of ASUSTeK Computer Inc. (“ASUS”).
Product warranty or service will not be extended if: (1) the product is repaired, modied or altered, unless
such repair, modication of alteration is authorized in writing by ASUS; or (2) the serial number of the
product is defaced or missing.
ASUS PROVIDES THIS MANUAL “AS IS” WITHOUT WARRANTY OF ANY KIND, EITHER EXPRESS
OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE IMPLIED WARRANTIES OR CONDITIONS OF
MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE. IN NO EVENT SHALL ASUS, ITS
DIRECTORS, OFFICERS, EMPLOYEES OR AGENTS BE LIABLE FOR ANY INDIRECT, SPECIAL,
INCIDENTAL, OR CONSEQUENTIAL DAMAGES (INCLUDING DAMAGES FOR LOSS OF PROFITS,
LOSS OF BUSINESS, LOSS OF USE OR DATA, INTERRUPTION OF BUSINESS AND THE LIKE),
EVEN IF ASUS HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES ARISING FROM ANY
DEFECT OR ERROR IN THIS MANUAL OR PRODUCT.
SPECIFICATIONS AND INFORMATION CONTAINED IN THIS MANUAL ARE FURNISHED FOR
INFORMATIONAL USE ONLY, AND ARE SUBJECT TO CHANGE AT ANY TIME WITHOUT NOTICE,
AND SHOULD NOT BE CONSTRUED AS A COMMITMENT BY ASUS. ASUS ASSUMES NO
RESPONSIBILITY OR LIABILITY FOR ANY ERRORS OR INACCURACIES THAT MAY APPEAR IN THIS
MANUAL, INCLUDING THE PRODUCTS AND SOFTWARE DESCRIBED IN IT.
Products and corporate names appearing in this manual may or may not be registered trademarks or
copyrights of their respective companies, and are used only for identication or explanation and to the
owners’ benet, without intent to infringe.

iii
Contents
Notices......................................................................................................... vi
Safety information ..................................................................................... vii
About this guide ........................................................................................ vii
P5QL-EM specications summary............................................................ ix
Chapter 1 Product introduction
1.1 Welcome! ...................................................................................... 1-1
1.2 Package contents......................................................................... 1-1
1.3 Special features............................................................................ 1-1
1.3.1 Product highlights ........................................................... 1-1
1.3.2 ASUS Special features ................................................... 1-2
1.4 Before you proceed ..................................................................... 1-4
1.5 Motherboard overview................................................................. 1-5
1.5.1 Placement direction ........................................................ 1-5
1.5.2 Screw holes .................................................................... 1-5
1.5.3 Motherboard layout ......................................................... 1-6
1.5.4 Layout contents............................................................... 1-7
1.6 Central Processing Unit (CPU) ................................................... 1-7
1.6.1 Installing the CPU ........................................................... 1-8
1.6.2 Installing the CPU heatsink and fan.............................. 1-10
1.6.3 Uninstalling the CPU heatsink and fan ..........................1-11
1.7 System memory ......................................................................... 1-11
1.7.1 Overview ........................................................................1-11
1.7.2 Memory congurations.................................................. 1-12
1.7.3 Installing a DIMM .......................................................... 1-16
1.7.4 Removing a DIMM ........................................................ 1-16
1.8 Expansion slots.......................................................................... 1-17
1.8.1 Installing an expansion card ......................................... 1-17
1.8.2 Conguring an expansion card ..................................... 1-17
1.8.4 PCI slots........................................................................ 1-17
1.8.5 PCI Express x1 slot....................................................... 1-17
1.8.6 PCI Express x16 slot..................................................... 1-17
1.9 Jumper ........................................................................................ 1-18
1.10 Connectors ................................................................................. 1-20
1.10.1 Rear panel connectors.................................................. 1-20
1.10.2 Internal connectors ....................................................... 1-22

iv
Contents
1.11 Software support........................................................................ 1-29
1.11.1 Installing an operating system ...................................... 1-29
1.11.2 Support DVD information .............................................. 1-29
Chapter 2 BIOS information
2.1 Managing and updating your BIOS ............................................ 2-1
2.1.1 ASUS Update utility ........................................................ 2-1
2.1.2 Creating a bootable oppy disk....................................... 2-2
2.1.3 ASUS EZ Flash 2 utility................................................... 2-3
2.1.4 AFUDOS utility................................................................ 2-4
2.1.5 ASUS CrashFree BIOS 3 utility ...................................... 2-5
2.2 BIOS setup program .................................................................... 2-7
2.2.1 BIOS menu screen.......................................................... 2-8
2.2.2 Menu bar......................................................................... 2-8
2.2.3 Navigation keys............................................................... 2-8
2.2.4 Menu items ..................................................................... 2-9
2.2.5 Sub-menu items.............................................................. 2-9
2.2.6 Conguration elds ......................................................... 2-9
2.2.7 Pop-up window ............................................................... 2-9
2.2.8 Scroll bar......................................................................... 2-9
2.2.9 General help ................................................................... 2-9
2.3 Main menu .................................................................................. 2-10
2.3.1 System Time ................................................................. 2-10
2.3.2 System Date ................................................................. 2-10
2.3.3 Legacy Diskette A ......................................................... 2-10
2.3.4 SATA 1~6 ...................................................................... 2-10
2.3.5 Storage Conguration ....................................................2-11
2.3.6 System Information ........................................................2-11
2.4 Advanced menu ......................................................................... 2-12
2.4.1 JumperFree Conguration ............................................ 2-12
2.4.2 CPU Conguration ........................................................ 2-13
2.4.3 Chipset.......................................................................... 2-15
2.4.4 Onboard Devices Conguration.................................... 2-16
2.4.5 USB Conguration ........................................................ 2-16
2.4.6 PCI PnP ........................................................................ 2-17
2.5 Power menu................................................................................ 2-17

v
Contents
2.5.1 Suspend Mode.............................................................. 2-18
2.5.2 ACPI 2.0 Support .......................................................... 2-18
2.5.3 ACPI APIC Support....................................................... 2-18
2.5.4 APM Conguration........................................................ 2-18
2.5.5 Hardware Monitor ......................................................... 2-19
2.6 Boot menu .................................................................................. 2-19
2.6.1 Boot Device Priority ...................................................... 2-20
2.6.2 Boot Settings Conguration .......................................... 2-20
2.6.3 Security ......................................................................... 2-20
2.7 Tools menu ................................................................................. 2-22
2.7.1 ASUS EZ Flash 2.......................................................... 2-22
2.7.2 Express Gate ................................................................ 2-22
2.7.3 AI NET 2........................................................................ 2-23
2.8 Exit menu.................................................................................... 2-23

vi
Notices
Federal Communications Commission Statement
This device complies with Part 15 of the FCC Rules. Operation is subject to the following two
conditions:
• This device may not cause harmful interference, and
• This device must accept any interference received including interference that may cause
undesired operation.
This equipment has been tested and found to comply with the limits for a Class B digital
device, pursuant to Part 15 of the FCC Rules. These limits are designed to provide
reasonable protection against harmful interference in a residential installation. This
equipment generates, uses and can radiate radio frequency energy and, if not installed
and used in accordance with manufacturer’s instructions, may cause harmful interference
to radio communications. However, there is no guarantee that interference will not occur
in a particular installation. If this equipment does cause harmful interference to radio or
television reception, which can be determined by turning the equipment off and on, the user
is encouraged to try to correct the interference by one or more of the following measures:
• Reorient or relocate the receiving antenna.
• Increase the separation between the equipment and receiver.
• Connect the equipment to an outlet on a circuit different from that to which the receiver is
connected.
• Consult the dealer or an experienced radio/TV technician for help.
Canadian Department of Communications Statement
This digital apparatus does not exceed the Class B limits for radio noise emissions from
digital apparatus set out in the Radio Interference Regulations of the Canadian Department
of Communications.
This class B digital apparatus complies with Canadian ICES-003.
The use of shielded cables for connection of the monitor to the graphics card is required
to assure compliance with FCC regulations. Changes or modications to this unit not
expressly approved by the party responsible for compliance could void the user’s authority
to operate this equipment.
DO NOT throw the motherboard in municipal waste. This product has been designed to
enable proper reuse of parts and recycling. This symbol of the crossed out wheeled bin
indicates that the product (electrical and electronic equipment) should not be placed in
municipal waste. Check local regulations for disposal of electronic products.
DO NOT throw the mercury-containing button cell battery in municipal waste. This symbol
of the crossed out wheeled bin indicates that the battery should not be placed in municipal
waste.

vii
Safety information
Electrical safety
• To prevent electrical shock hazard, disconnect the power cable from the electrical outlet
before relocating the system.
• When adding or removing devices to or from the system, ensure that the power cables
for the devices are unplugged before the signal cables are connected. If possible,
disconnect all power cables from the existing system before you add a device.
• Before connecting or removing signal cables from the motherboard, ensure that all
power cables are unplugged.
• Seek professional assistance before using an adpater or extension cord. These devices
could interrupt the grounding circuit.
• Make sure that your power supply is set to the correct voltage in your area. If you are
not sure about the voltage of the electrical outlet you are using, contact your local power
company.
• If the power supply is broken, do not try to x it by yourself. Contact a qualied service
technician or your retailer.
Operation safety
• Before installing the motherboard and adding devices on it, carefully read all the manuals
that came with the package.
• Before using the product, make sure all cables are correctly connected and the power
cables are not damaged. If you detect any damage, contact your dealer immediately.
• To avoid short circuits, keep paper clips, screws, and staples away from connectors,
slots, sockets and circuitry.
• Avoid dust, humidity, and temperature extremes. Do not place the product in any area
where it may become wet.
• Place the product on a stable surface.
• If you encounter technical problems with the product, contact a qualied service
technician or your retailer.
About this guide
This user guide contains the information you need when installing and conguring the
motherboard.
How this guide is organized
This guide contains the following parts:
• Chapter 1: Product introduction
This chapter describes the features of the motherboard and the new technology it
supports.
• Chapter 2: BIOS information
This chapter tells how to change system settings through the BIOS Setup menus.
Detailed descriptions of the BIOS parameters are also provided.

viii
Where to nd more information
Refer to the following sources for additional information and for product and software
updates.
1. ASUS websites
The ASUS website provides updated information on ASUS hardware and software
products. Refer to the ASUS contact information.
2. Optional documentation
Your product package may include optional documentation, such as warranty yers,
that may have been added by your dealer. These documents are not part of the
standard package.
Conventions used in this guide
To make sure that you perform certain tasks properly, take note of the following symbols used
throughout this manual.
DANGER/WARNING: Information to prevent injury to yourself
when trying to complete a task.
CAUTION: Information to prevent damage to the components
when trying to complete a task.
NOTE: Tips and additional information to help you complete a
task.
IMPORTANT: Instructions that you MUST follow to complete a
task.
Typography
Bold text Indicates a menu or an item to select.
Italics Used to emphasize a word or a phrase.
<Key> Keys enclosed in the less-than and greater-than sign means
that you must press the enclosed key.
Example: <Enter> means that you must press the Enter or
Return key.
<Key1>+<Key2>+<Key3> If you must press two or more keys simultaneously, the key
names are linked with a plus sign (+).
Example: <Ctrl>+<Alt>+<D>
Command Means that you must type the command exactly as shown,
then supply the required item or value enclosed in brackets.
Example: At the DOS prompt, type the command line:
afudos /i[lename]
afudos /iP5QLEM.ROM

ix
P5QL-EM specications summary
(continued on the next page)
CPU LGA775 socket for Intel®Core™ 2 Quad / Core™ 2 Duo
/ Core ™ 2 Extreme / Pentium®Extreme / Pentium® D
/ Pentium®4 / Celeron®processors
Supports Intel®next generation 45nm CPU
Supports Enhanced Intel SpeedStep®Technology (EIST)
Supports Intel®Hyper-Threading Technology
*Refer to www.asus.com for Intel CPU support list
Chipset Intel G43
Intel ICH10
Front Side Bus 1333 / 1066 / 800 MHz
Memory Dual-channel memory architecture
4 x 240-pin DIMM sockets support unbufferred non-ECC
DDR2-1066 (O.C.) / 800 / 667 / memory
modules
Supports up to 8 GB system memory
* Due to chipset limitation, this motherboard only
supports up to the total of four ranks(four sides in total)
of RAM at max.
* Supports two DIMM modules only for yellow DIMMs
when overclock to DDR2-1066.
Graphics Integrated Intel GMA X4500 graphics with DirectX10
support
Maximum shared memory of 352MB
Supports HDMI™ Technology with HDCP compliant with
max. resolution 1920 x 1080p (@ 60Hz)
Supports DVI-D with HDCP compliant with max.
resolution 1900 x 1200 (@60Hz)
Supports RGB with max. resolution 2048 x 1536 (@75Hz)
Dual VGA output support
DVI & RGB
RGB & HDMI
DVI & HDMI
Expansion Slots 1 x PCI Express x16 slot
2 x PCI Express x1 slots
1 x PCI slot
Supports PCIe 2.0/1.0 Architecature
LAN PCIe Gb LAN controller featuring AI NET 2
USB Max. 12 USB 2.0/1.1 ports (6 ports at mid-board, 6 ports
at back panel)
BIOS features 8 MB Flash ROM, AMI BIOS, Special H/W write protection,
PnP, DMI v2.0, WfM2.0, SMBIOS 2.5, ACPI
Audio Realtek ALC1200 8-channel High Denition Audio
CODEC
Supports S/PDIF out interface
Audio Jack-dectect, Multi-Streaming and Jack-Retasking
Technology

x
P5QL-EM specications summary
*Specications are subject to change without notice.
Storage ICH10 Southbridge:
- 6 x Serial ATA 3Gb/s devices
Ext PATA and SATA controller supports:
- 1 x UltraDMA 133/100 for up to 2 PATA devices
- 1 x External Serial ATA 3Gb/s (SATA On-the-go)
ASUS overclocking
features
SFS (Stepless Frequency Selection):
- FSB turning from 200MHz up to 600MHz at 1MHz
increment
ASUS C.P.R. (CPU Parameter Recall)
ASUS Special Features ASUS CrashFree BIOS 3
ASUS Q-Fan
ASUS EZ Flash 2
ASUS MyLogo 2
ASUS AI Nap
ASUS EPU
ASUS Express Gate
Rear panel 1 x DVI port
1 x HDMI port
1 x VGA port
1 x External Serial ATA
1 x IEEE 1394a port
1 x PS/2 Mouse / Keyboard port
1 x LAN (RJ45) port
6 x USB 2.0/1.1 ports
8-channel Audio I/O port
Internal connectors 1 x High denition Front Panel Audio connector
1 x S/PDIF out connector
1 x Chassis intrusion connector
1 x System panel connector
3 x USB connectors for additional six USB 2.0 ports
1 x CPU/ 1 x Chassis/ 1 x Power Fan connector
1 x CD audio in connector
1 x Floppy disk drive connector
1 x IDE connector
1 x COM connector
1 x LPT connector
1 x 24-pin ATX power connector
1 x 4-pin ATX 12 V power connector
Manageability WOL by PME, WOR by PME, WOR by Ring
Support DVD Drivers
ASUS PC Probe II
ASUS LiveUpdate Utility
Supported OS Windows Vista/XP
Accessories 2 x Serial ATA cables
1 x 2 in 1 Serial ATA power cable
1 x UltraDMA 133/100 cable
1 x FDD cable
1 x I/O shield
User manual
Form factor uATX Form Factor: 9.6 in x 9.6 in (24.4 cm x 24.4 cm)

ASUS P5QL-EM 1-1
Chapter 1
Product introduction
1.1 Welcome!
Thank you for buying an ASUS®P5QL-EM motherboard!
The motherboard delivers a host of new features and latest technologies, making it another
standout in the long line of ASUS quality motherboards!
Before you start installing the motherboard, and hardware devices on it, check the items in
your package with the list below.
1.2 Package contents
Check your motherboard package for the following items.
If any of the above items is damaged or missing, contact your retailer.
1.3 Special features
1.3.1 Product highlights
Green ASUS
This motherboard and its packaging comply with the European Union’s Restriction on the
use of Hazardous Substances (RoHS). This is in line with the ASUS vision of creating
environment-friendly and recyclable products/packaging to safeguard consumers’ health
while minimizing the impact on the environment.
LGA775 Intel®Core™2 and Quad-core Processor Ready
This motherboard supports the latest Intel®Core™2 processors in LGA775 package. It
also can support Intel®next generation 45nm Multi-Core CPU. With new Intel®Core™
microarchitecture technology and 1333/1066/800 MHz FSB, Intel®Core™2 processor is one
of the most powerful and efcient CPU in the world.
Motherboard ASUS P5QL-EM motherboard
Cables 2 x Serial ATA cables
1 x Ultra DMA 133 / 100 cable
1 x 2 in 1 Serial ATA power cable
1 x Floppy disk drive cable
Accessories 1 x I/O shield
Application DVD ASUS motherboard support DVD
Documentation User Manual

1-2 Chapter 1: Product introduction
Dual channel DDR2 1066(O.C.)
The motherboard supports DDR2 memory that features data transfer rates of 667 / 800 / 1066
(overclocking) MHz to meet the higher bandwidth requirements of the latest 3D graphics,
multimedia, and Internet applications.
PCIe 2.0 support
This motherboard supports the latest PCIe 2.0 devices for double speed and bandwidth
which enhances system performance.
HDMI™ Interface
HDMI (High-Denition Multimedia Interface) is the rst and only industry-supported,
uncompressed, all digital audio and video interface via a single cable and is HDCP compliant
allowing playback of HD DVD, Blu-ray Disc and other protected content.The interface of this
motherboard supports dual VGA output both HDMI and RGB.
Serial ATA 3 Gb/s technology and SATA-On-the-Go
This motherboard supports next-generation SATA hard drives based on the Serial
ATA(SATA) 3Gb/s storage specication,delivering enhanced scalability and doubling the bus
bandwidth for high -speed data retrieval and saves.The external SATA port located at the
back I/O provide smart setup and hot-plug function.Easily backup photos,videos and other
entertainment contents to external devices.
High Denition Audio
Enjoy high-quality sound system on your PC! The onboard 8-channel HD audio (High
Denition Audio, previously codenamed Azalia) CODEC enables high-quality audio output,
jack-detect feature automatically.
IEEE 1394a
IEEE 1394a interface provides high speed digital interface for audio/video appliances such as
digital television, digital video camcorders, storage peripherals & other PC portable devices.
Uses 100% All High-quality conductive Polymer Capacitors!
This motherboard uses all high-quality conductive polymer capacitors onboard for durability,
improved lifespan, and enhanced thermal capacity.
1.3.2 ASUS Special features
ASUS EPU
The ASUS EPU utilizes innovative technology to digitally monitor and netune the CPU
power supply with improved VR responses in heavy or light loadings.

ASUS P5QL-EM 1-3
ASUS AI Nap
Minimize noise and power consumption when temporarily away! With AI Nap, users can
instantly snooze your PC without terminating the tasks. System will continue operating at
minimum power and noise when user is temporarily away. It keeps downloading les or
running applications in quietest state while you´re sleeping. Simply click keyboard or mouse,
you can swiftly wake up the system in few seconds.
ASUS Q-Fan technology
The ASUS Q-Fan technology smartly adjusts the fan speeds according to the system loading
to ensure quiet, cool, and efcient operation.
C.P.R.(CPU Parameter Recall)
When the system hangs due to overclocking failure, there is no need to open the case to
clear CMOS data. Just simply restart the system, the BIOS would show the previous setting
and then users can amend the CPU setting again.
ASUS MyLogo2™
This feature allows you to convert your favorite photo into a 256-color boot logo for a more
colorful and vivid image on your screen. See page 2-20 for details.
ASUS EZ Flash 2
EZ Flash 2 is a user-friendly BIOS update utility. Simply press the predened hotkey to launch
the utility and update the BIOS without entering the OS. Update your BIOS easily without
preparing a bootable diskette or using an OS-based ash utility. See page 2-3 for details.
ASUS CrashFree BIOS 3
The ASUS CrashFree BIOS 3 allows users to restore corrupted BIOS data from a USB
ash disk containing the BIOS le. This utility saves users’ the cost and hassle of buying a
replacement BIOS chip.
ASUS Express Gate
Taking only 5 seconds to go online from bootup, Express Gate is the one-stop gateway to
instant fun! It’s a unique motherboard built-in OS. You can utilize the most popular Instant
Messengers (IM) like MSN, Skype, Google talk, QQ, and Yahoo! Messenger to keep in touch
with friends, or quickly check on the weather and E-mails just before leaving your house.
What’s more, the user-friendly picture manager lets you view your pictures without entering
Windows at anytime!
• The actual boot time depends on the system conguration.
• ASUS Express Gate supports le uploading from SATA HDDs, ODDs and USB drive
and downloading to USB drives only.

1-4 Chapter 1: Product introduction
1.4 Before you proceed
Take note of the following precautions before you install motherboard components or change
any motherboard settings.
• Unplug the power cord from the wall socket before touching any component.
• Use a grounded wrist strap or touch a safely grounded object or a metal object, such
as the power supply case, before handling components to avoid damaging them due to
static electricity.
• Hold components by the edges to avoid touching the ICs on them.
• Whenever you uninstall any component, place it on a grounded antistatic pad or in the
bag that came with the component.
• Before you install or remove any component, ensure that the ATX power supply is
switched off or the power cord is detached from the power supply. Failure to do so may
cause severe damage to the motherboard, peripherals, and/or components.
Onboard LED
The motherboard comes with a standby power LED that lights up to indicate that the
system is ON, in sleep mode, or in soft-off mode. This is a reminder that you must
shut down the system and unplug the power cable before removing or plugging in any
motherboard component. The illustration below shows the location of the onboard LED.
P5QL-EM Onboard LED
P5QL-EM
R
SB_PWR
ON
Standby
Power
OFF
Powered
Off

ASUS P5QL-EM 1-5
1.5 Motherboard overview
Before you install the motherboard, study the conguration of your chassis to ensure that the
motherboard ts into it.
Ensure that you unplug the power cord before installing or removing the motherboard.
Failure to do so can cause you physical injury and damage motherboard components.
1.5.1 Placement direction
When installing the motherboard, make sure that you place it into the chassis in the correct
orientation. The edge with external ports goes to the rear part of the chassis as indicated in
the image below.
1.5.2 Screw holes
Place eight screws into the holes indicated by circles to secure the motherboard to the
chassis.
Do not overtighten the screws! Doing so can damage the motherboard.
Place this side towards
the rear of the chassis
P5QL-EM
R

1-6 Chapter 1: Product introduction
1.5.3 Motherboard layout
Refer to 1.10 Connectors for more information about rear panel ports and internal
connectors.
P5QL-EM
R
24.4cm(9.6in)
PCIEX16
PCIEX1_2
PCI1
PCIEX1_1
USB1112 USB910
USBPW9-12
USBPW78
USB78
PS2_USBPW5-6 USBPW1-4
8Mb
BIOS
Super I/O
CR2032 3V
Lithium Cell
CMOS Power
24.4cm(9.6in)
PS/2KBMS
USB56
RTL
81111C
LGA775
PWR_FAN
CPU_FAN
Intel ICH10
Marvell
6111B2
Intel G43
FLOPPY
COM1
SATA12
SATA34
SATA56
CLRTC
SB_PWR
CD
DDR2 DIMM_A1 (64 bit,240-pin module) DDR2 DIMM_A2 (64 bit,240-pin module) DDR2 DIMM_B1 (64 bit,240-pin module) DDR2 DIMM_B2 (64 bit,240-pin module)
PANEL
JMB381
PRI_EIDE
RTM870T-945
ALC1200
LPT
AAFP
SPDIF_OUT CHASSIS
LAN1_USB12
1394
ESATA
USB34
AUDIO
HDMI
DVI_VGA
CHA_FAN
ATX12V
EATXPWR
2 3 31 54 6
1012113141516
17
11
7
2
8
1
5
18
9

ASUS P5QL-EM 1-7
1.5.4 Layout contents
Connectors/Jumpers/Slots Page
1. USB device wake-up (3-pin PS2_USBPW) 1-19
2. ATX power connectors (24-pin EATXPWR, 4-pin ATX12V) 1-27
3. LGA775 CPU Socket 1-7
4. DDR2 DIMM slots 1-11
5. CPU, Chassis, and Power fan connectors (4-pin CPU_FAN, 3-pin
CHA_FAN, 3-pin PWR_FAN))
1-24
6. Serial port connectors (10-1 pin COM1) 1-26
7. Floppy disk drive connector (34-1 pin FLOPPY) 1-22
8. LPT connector (26-1 pin LPT) 1-26
9. ICH10 Serial ATA connectors (7-pin SATA1-6) 1-22
10. IDE connector (40-1 pin PRI_EIDE) 1-23
11. USB connectors (10-1 pin USB78, USB910, and USB1112) 1-24
12. Clear RTC RAM (3-pin CLRTC) 1-18
13. System panel connector (20-8 pin PANEL) 1-28
14. Standby power LED 1-4
15. Optical drive audio connector (4-pin CD) 1-27
16. Front panel audio connector (10-1 pin AAFP) 1-25
17. Digital audio connector (4-1 pin SPDIF_OUT) 1-23
18. Chassis intrusion connector (4-1 pin CHASSIS) 1-25
1.6 Central Processing Unit (CPU)
The motherboard comes with a surface mount LGA775 socket designed for the Core™2
Quad / Core™2 Extreme / Core™2 Duo / Pentium®D / Pentium®Extreme / Pentium®4 and
Celeron® processors.
• Ensure that all power cables are unplugged before installing the CPU.
• Connect the chassis fan cable to the CHA_FAN connector to ensure system stability.
• Upon purchase of the motherboard, make sure that the PnP cap is on the socket and
the socket contacts are not bent. Contact your retailer immediately if the PnP cap
is missing, or if you see any damage to the PnP cap/socket contacts/motherboard
components. ASUS will shoulder the cost of repair only if the damage is shipment/
transit-related.
• Keep the cap after installing the motherboard. ASUS will process Return Merchandise
Authorization (RMA) requests only if the motherboard comes with the cap on the
LGA775 socket.
• The product warranty does not cover damage to the socket contacts resulting from
incorrect CPU installation/removal, or misplacement/loss/incorrect removal of the PnP
cap.

1-8 Chapter 1: Product introduction
1.6.1 Installing the CPU
To install a CPU:
1. Locate the CPU socket on the motherboard.
Before installing the CPU, ensure that the socket box is facing towards you and the load
lever is on your left.
To prevent damage to the socket
pins, do not remove the PnP cap
unless you are installing a CPU.
2. Press the load lever with your thumb
(A), then move it to the left (B) until it is
released from the retention tab.
4. Lift the load plate with your thumb and
forenger to a 100º angle (4A), then
push the PnP cap from the load plate
window to remove (4B).
3. Lift the load lever in the direction of the
arrow to a 135º angle.
A
B
Load lever
Retention tab
Load plate
PnP cap
4A
4B
3
P5QL-EM CPU Socket 775
P5QL-EM
R

ASUS P5QL-EM 1-9
5. Position the CPU over the socket,
ensuring that the gold triangle is on the
bottom-left corner of the socket then t
the socket alignment key into the CPU
notch.
6. Apply several drops of Thermal Interface
Material to the exposed area of the CPU
that the heatsink will be in contact with,
ensuring that it is spread in an even thin
layer.
DO NOT eat the Thermal Interface Material. If it gets into your eyes or touches your skin,
ensure that you wash it off immediately, and seek professional medical help.
Some heatsinks come with pre-
applied thermal paste. If so, skip this
step.
To prevent contaminating the paste, DO NOT spread the paste with your nger directly.
7. Close the load plate (A), then push
the load lever (B) until it snaps into the
retention tab.
The motherboard supports Intel®
LGA775 processors with the
Intel®Enhanced Intel SpeedStep®
Technology (EIST) and Hyper-
Threading Technology.
Gold
triangle
mark
Alignment key
CPU notch
A
B

1-10 Chapter 1: Product introduction
1.6.2 Installing the CPU heatsink and fan
The Intel®LGA775 processor requires a specially designed heatsink and fan assembly to
ensure optimum thermal condition and performance.
• When you buy a boxed Intel®processor, the package includes the CPU fan and
heatsink assembly. If you buy a CPU separately, ensure that you use only Intel®-certied
multi-directional heatsink and fan.
• Your Intel®LGA775 heatsink and fan assembly comes in a push-pin design and requires
no tool to install.
• If you purchased a separate CPU heatsink and fan assembly, make sure that you have
properly applied Thermal Interface Material to the CPU heatsink or CPU before you
install the heatsink and fan assembly.
Ensure that you have installed the motherboard to the chassis before you install the CPU
fan and heatsink assembly.
The type of CPU heatsink and fan assembly may differ, but the installation steps and
fucntions should remain the same. The illustration above is for reference only.
To install the CPU heatsink and fan:
1. Place the heatsink on top of the installed
CPU, making sure that the four fasteners
match the holes on the motherboard.
2. Push down two fasteners at a time in a
diagonal sequence to secure the heatsink
and fan assembly in place.
3. Connect the CPU fan cable to the connector on the motherboard labeled CPU_FAN.
Do not forget to connect
the CPU fan connector!
Hardware monitoring errors
can occur if you fail to plug
this connector.
A
A
B
B
1
1
AB
BA
P5QL-EM CPU Fan Connector
P5QL-EM
R
CPU_FAN
GND
CPU FAN PWR
CPU FAN IN
CPU FAN PWM