Asus P2B User manual

R
P2B
Pentium®II Motherboard
USER’S MANUAL

2ASUS P2B User’s Manual
USER'S NOTICE
Product Name: ASUS P2B
Manual Revision: 1.02+ E307
Release Date: March 1999
No part of this manual, including the products and software described in it, may be repro-
duced, 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”).
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 MERCHANTABILITYOR FITNESS FORAPAR-
TICULAR PURPOSE. IN NO EVENT SHALL ASUS, ITS DIRECTORS, OFFICERS,
EMPLOYEES OR AGENTS BE LIABLE FOR ANY INDIRECT, SPECIAL, INCIDEN-
TAL, OR CONSEQUENTIAL DAMAGES (INCLUDING DAMAGES FOR LOSS OF
PROFITS, LOSS OF BUSINESS, LOSS OF USE OR DATA, INTERRUPTION OF BUSI-
NESS 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.
Product warranty or service will not be extended if: (1) the product is repaired, modified or
altered, unless such repair, modification of alteration is authorized in writing byASUS; or (2)
the serial number of the product is defaced or missing.
Products and corporate names appearing in this manual may or may not be registered trade-
marks or copyrights of their respective companies, and are used only for identification or
explanation and to the owners’ benefit, without intent to infringe.
• Intel, LANDesk, and Pentium are registered trademarks of Intel Corporation.
• IBM and OS/2 are registered trademarks of International Business Machines.
• Symbios is a registered trademark of Symbios Logic Corporation.
• Windows and MS-DOS are registered trademarks of Microsoft Corporation.
• Adobe and Acrobat are registered trademarks of Adobe Systems Incorporated.
The product name and revision number are both printed on the product itself. Manual revi-
sions are released for each product design represented by the digit before and after the period
of the manual revision number. Manual updates are represented by the third digit in the manual
revision number.
For previous or updated manuals, BIOS, drivers, or product release information, contactASUS
at http://www.asus.com.tw or through any of the means indicated on the following page.
SPECIFICATIONS AND INFORMATION CONTAINED IN THIS MANUAL ARE FUR-
NISHED FOR INFORMATIONAL USE ONLY, AND ARE SUBJECT TO CHANGE AT
ANY TIME WITHOUT NOTICE, AND SHOULD NOT BE CONSTRUED AS A COM-
MITMENT BY ASUS. ASUS ASSUMES NO RESPONSIBILITY OR LIABILITY FOR
ANYERRORS ORINACCURACIESTHATMAYAPPEARINTHISMANUAL, INCLUD-
ING THE PRODUCTS AND SOFTWARE DESCRIBED IN IT.
Copyright © 1999 ASUSTeK COMPUTER INC. All Rights Reserved.

ASUS P2B User’s Manual 3
ASUS CONTACT INFORMATION
ASUSTeK COMPUTER INC. (Asia-Pacific)
Marketing
Address: 150 Li-Te Road, Peitou, Taipei, Taiwan 112
Telephone: [phone]
Fax: [phone]
Email: [email protected]
Technical Support
Tel (English): [phone] ext. 706
Tel (Chinese): [phone] ext. 111
Fax: [phone]
Email: [email protected]
Newsgroup: news2.asus.com.tw
WWW: www.asus.com.tw
FTP: ftp.asus.com.tw/pub/ASUS
ASUS COMPUTER INTERNATIONAL (America)
Marketing
Address: 6737 Mowry Avenue, Mowry Business Center, Building 2
Newark, CA 94560, USA
Fax: [phone]
Email: [email protected]
Technical Support
Fax: [phone]
BBS: [phone]
Email: [email protected]
WWW: www.asus.com
FTP: ftp.asus.com.tw/pub/ASUS
ASUS COMPUTER GmbH (Europe)
Marketing
Address: Harkort Str. 25, 40880 Ratingen, BRD, Germany
Telephone: [phone]
Fax: [phone]
Email: [email protected]
Technical Support
Hotline: [phone]
BBS: 49-2102-448690
Email: [email protected]
WWW: www.asuscom.de
FTP: ftp.asuscom.de/pub/ASUSCOM

4ASUS P2B User’s Manual
CONTENTS
I. INTRODUCTION............................................................................... 7
How this Manual is Organized ........................................................... 7
Item Checklist ..................................................................................... 7
II. FEATURES ........................................................................................ 8
Features of the ASUS P2B Motherboard ............................................ 8
The ASUS P2B Motherboard .......................................................... 9
III. HARDWARE SETUP.................................................................... 10
Layout of the ASUS P2B Motherboard ............................................ 10
Installation Steps............................................................................... 12
Jumpers ............................................................................................. 12
Jumper Settings ............................................................................. 13
System Memory (DIMM) ................................................................. 17
SPD Support ................................................................................ 17
DIMM Memory Installation Procedures:.................................... 18
Central Processing Unit (CPU)......................................................... 19
Universal Retention Mechanism ................................................. 19
Heatsinks ..................................................................................... 19
Installing the Processor ................................................................. 20
ASUS Smart Thermal Solutions ................................................. 22
Recommended Heatsinks for Slot 1 Processors.......................... 23
Expansion Cards ............................................................................... 24
Expansion Card Installation Procedure ....................................... 24
Assigning IRQs for Expansion Cards ......................................... 24
Assigning DMA Channels for ISA Cards ................................... 25
ISA Cards and Hardware Monitor............................................... 25
External Connectors.......................................................................... 26
Power Connection Procedures .......................................................... 33
Power Connection Procedures .......................................................... 33

ASUS P2B User’s Manual 5
CONTENTS
IV. BIOS SETUP................................................................................... 34
Managing and Updating Your BIOS ................................................. 34
Upon First Use of the Computer System....................................... 34
Updating BIOS Procedures ........................................................... 35
Managing and Updating Your Motherboard’s BIOS ..................... 36
BIOS Setup ....................................................................................... 37
Load Defaults .............................................................................. 38
Standard CMOS Setup .................................................................. 38
Details of Standard CMOS Setup: .............................................. 38
BIOS Features Setup ..................................................................... 41
Details of BIOS Features Setup .................................................. 41
Chipset Features Setup .................................................................. 44
Details of Chipset Features Setup ............................................... 44
Power Management Setup ............................................................. 47
Details of Power Management Setup .......................................... 47
PNP and PCI Setup........................................................................ 50
Details of PNP and PCI Setup..................................................... 50
Load BIOS Defaults ...................................................................... 52
Load Setup Defaults ...................................................................... 52
Supervisor Password and User Password...................................... 53
IDE HDD Auto Detection ............................................................. 54
Save & Exit Setup ......................................................................... 55
Exit Without Saving ...................................................................... 55
V. SUPPORT SOFTWARE................................................................. 56
Desktop Management Interface (DMI)............................................. 56
Introducing the ASUS DMI Configuration Utility...................... 56
System Requirements.................................................................. 56
Using the ASUS DMI Configuration Utility............................... 57
VI. APPENDIX ..................................................................................... 59
The ASUS CIDB Chassis Intrusion Sensor Module......................... 59
The ASUS S370 CPU Card .............................................................. 61
ASUS PCI-L101 Fast Ethernet Card ................................................ 63
Glossary ............................................................................................ 65

6ASUS P2B User’s Manual
FCC & DOC COMPLIANCE
FederalCommunications Commission Statement
This device complies with FCC Rules Part 15. 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 installa-
tion. 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 inter-
ference by one or more of the following measures:
• Re-orient 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.
WARNING! Any changes or modifications to this product not expressly ap-
proved by the manufacturer could void any assurances of safety or performance
and could result in violation of Part 15 of the FCC Rules.
CanadianDepartment of CommunicationsStatement
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 Cana-
dian Department of Communications.
This Class B digital apparatus complies with Canadian ICES-003.
CetappareilnumériquedelaclasseBestconformeàlanormeNMB-003duCanada.

ASUS P2B User’s Manual 7
I. INTRODUCTION
I. INTRODUCTION
Manual / Checklist
How this Manual is Organized
This manual is divided into the following sections:
I. Introduction: Manual information and checklist
II. Features: Information and specifications concerning this product
III. Hardware Setup: Instructions on setting up the motherboard
IV. BIOS Setup: Instructions on setting up the BIOS software
V. Support Software: Information on the included support software
VI. Appendix Optional items and general reference
Item Checklist
Please check that your package is complete. If you discover damaged or missing
items, please contact your retailer.
(1) ASUS Motherboard
(1) Universal Retention Mechanism for SECC/SECC2/SEPP
(1) IDE ribbon cable for master and slave drives
(1) Floppy ribbon cable for (1) 5.25inch floppy and (2) 3.5inch floppies
(1) Bag of spare jumper caps
(1) Support CD with drivers and utilities
(1) User’s manual
S-P2FAN or P2T-Cable for Slot 1 processors
IrDA-compliant infrared module (optional)
ASUS PCI-L101 Wake-on-LAN 10/100 Ethernet Card (optional)

ASUS P2B User’s Manual8
Features of the ASUS P2B Motherboard
The ASUS P2B is carefully designed for the demanding PC user who wants ad-
vanced features processed by the fastest CPU.
•Multi-Speed: Supports Intel Pentium
®
III (450MHz and faster), Pentium
®
II (233MHz
to 450MHz), and Celeron
TM
(266MHz and faster) processors.
•Multi-Cache:Supports processors with 512, 128, or 0KB Pipelined Burst Level 2 cache.
•Intel AGPset: Features Intel’s 440BX AGPset with I/O subsystems and front-side bus
(FSB) platform, which boosts the traditional 66-MHz internal bus speed to 100MHz.
•Enhanced ACPI and Anti-Boot Virus BIOS: Features a programmable BIOS, offering
enhancedACPIforWindows98compatibility,built-inhardware-basedvirusprotectionthrough
Trend ChipAway Virus, and autodetection of most devices for virtually automatic setup.
•PC100 Memory Support: Equipped with three DIMM sockets to support Intel PC100-
compliant SDRAMs (8, 16, 32, 64, 128, or 256MB) up to 768MB. These new SDRAMs
are necessary to meet the critical enhanced 100MHz bus speed requirement.
•Thermal Sensor Connector with Optional Sensor: Accurately detects the CPU tem-
perature of processors with the ASUS Smart Fan or the Intel boxed processor heatsink
with fan when connected to an ASUS P2T-Cable.
•Wake-On-LAN: Supports Wake-On–LAN activity with special network cards, such as
the ASUS PCI-L101 10/100 Fast Ethernet PCI card.
•AGP Slot: Supports Accelerated Graphics Port cards for high performance, component
level interconnect targeted at 3D graphical display applications.
•SB-Link™: Features Creative’s SB-Link™, allowing SB16 compatibility, using Intel’s
PC-PCI DMAand serialized IRQ protocols, to AWE64D or compatible PCI audio cards.
•SMBus: Features the System Management Bus interface, which is used to physically
transport commands and information between SMBus devices.
•PCI & ISA Expansion Slots: Provides four 32-bit PCI and three 16-bit ISA slots.
•Intelligence: Supports Keyboard Power Up, Fan Status Monitoring and Alarm, Tem-
perature Monitoring and Alert, Voltage Monitoring and Alert, System Resources Alert,
Intel LANDesk Client Manager (LDCM), and ASUS PC Probe software.
•SuperMulti-I/O: Provides two high-speed UART compatible serial ports and one paral-
lel port with EPP and ECP capabilities. UART2 can also be directed from COM2 to the
Infrared Module for wireless connections.
• Desktop Management Interface (DMI): Supports DMI through BIOS, which allows
hardware to communicate within a standard protocol creating a higher level of compat-
ibility. (Requires DMI-enabled components.) (See section V)
•Ultra DMA/33 Bus Master IDE: Comes with an onboard PCI Bus Master IDE control-
lerwith two connectors thatsupportfour IDE devicesintwochannels, supports UltraDMA/
33, PIO Modes 3 and 4 and Bus Master IDE DMA Mode 2, and supports Enhanced IDE
devices, such as Tape Backup, CD-ROM, and LS-120 drives.
•UniversalRetention Mechanism:Supports a Pentium
®
II processor packaged in a Single
Edge Contact Cartridge (SECC/SECC2) or a Celeron
TM
processor packaged in a Single
Edge Processor Package (SEPP).
•SCSI BIOS: Supports optionalASUS SCSI cards through onboard SYMBIOS firmware.
•IrDA: Supports an optional infrared port module for wireless interface.
•Concurrent PCI:Allows multiple PCI transfers from PCI master buses to memory to CPU.
II. FEATURES
Specifications
II. FEATURES

ASUS P2B User’s Manual 9
The ASUS P2B Motherboard
II. FEATURES
II. FEATURES
Motherboard Parts
T: USB Port 1
B: USB Port 2
B: COM 1
B: COM 2
Programmable
2Mbit Flash EEROM
3ISA Slots
T: PS/2 Mouse
B: PS/2 Keyboard
T: Parallel
B: Serial
3 DIMM Sockets
Intel 440BXAGPset
CPU
Slot 1
ATX Power
Connector
4 PCI Slots
Universal Folding
Retention Mechanism
Accelerated
Graphics Port
Wake-On-LAN
Connector
Hardware
MonitoringASIC

ASUS P2B User’s Manual10
III. HARDWARE SETUP
Layout of the ASUS P2B Motherboard
Board Layout
III. H/W SETUP
FLOPPY
SECONDARY IDE
PRIMARY IDE
CR2032 3V
Lithium Cell
(BIOS Power)
CPU_FAN
DIMM Socket 1 (64/72 bit, 168 pin module) DIMM Socket 2 (64/72 bit, 168 pin module) DIMM Socket 3 (64/72 bit, 168 pin module)
Accelerated Graphics Port
PCI Slot 4
ISA Slot 3
Intel PIIX4E
PCIset
Intel
440BX
AGPset
Flash EEPROM (Programable BIOS)
PWR_FAN
CHA_FAN
Hardware
Monitor
ATX Power Conenctor
CPU Slot 1
Panel Connectors
Infrared Connector
IDE LED
USB
PS/2
TOP:
USB 1
BOTTOM:
USB 2
Multi-I/O
R
Wake-On-LAN
Connector
BUS FREQ
BF2
BF3
BF1
BF0
CLRTC
BUS FREQ
FS1
FS2
FS0
ISA Slot 1
ISA Slot 2
PCI Slot 3
PCI Slot 2
PCI Slot 1
COM 1
Parallel Port
COM 2
TOP:
Mouse
BOTTOM:
Keyboard
Keyboard Power
ASUS
ASIC
SMB Connector
SBLINK
JTPWR
CHASIS
JTCPU

ASUS P2B User’s Manual 11
III. HARDWARE SETUP
Jumpers
1) CLRTC p. 13 Clear Real Time Clock (RTC) RAM (Short/Clear CMOS)
2) KBPWR p. 13 Keyboard Power
3) FS0, FS1, FS2 p. 14 CPU External Clock (BUS) Frequency Selection
4) BF0, BF1, BF2, BF3 p. 14 CPU Core:BUS Frequency Multiple
Expansion Slots/Sockets
1) System Memory p. 17 System Memory Support
2) DIMM Sockets p. 18 DIMM Memory Module Support
3) CPU Slot 1 p.19 Pentium II/Celeron CPU Support
4) SLOT1, SLOT2, SLOT3 p. 24 16-bit ISA Bus Expansion Slots
*
5) PCI1, PCI2,PCI3, PCI4 p. 24 32-bit PCI Bus Expansion Slots
6) AGP p.25 Accelerated Graphics Port
Hardware Monitor
1) JTPWR, JTCPU p. 23 Thermal Sensor Connector
Connectors
1) PS2KBMS p. 26 PS/2 Keyboard Connector (6-pin female)
2) PS2KBMS p. 26 PS/2 Mouse Connector (6-pin female)
3) PARALLEL p. 27 Parallel (Printer) Port Connector (25-pin female)
4) COM1, COM2 p. 27 Serial Port COM1 & COM2 (two 9-pin male)
5) FLOPPY p. 27 Floppy Drive Connector (34-pin block)
6) USB p. 28 Universal Serial BUS Ports 1 & 2 (two 4-pin female)
7) Primary/Secondary IDE p. 28 Primary/Secondary IDE Connector (40-pin blocks)
8) IDELED p. 28 IDE LED Activity Light (2 pins)
9) CHA_, PWR_, CPU_FAN p. 29 Chassis, Power Supply, CPU Fan Power Lead (3-pin block)
10) CHASIS p. 29 Chassis Intrusion Alarm Lead (4-1 pins)
11) IR p. 30 Infrared Port Module Connector (5 pins)
12) ATXPWR p. 30 ATX Motherboard Power Connector (20-pin block)
13) WOL_CON p. 31 Wake on LAN Connector (3 pins)
14) SBLINK p. 31 SB-Link™ Connector (6-1 pins)
15) SMB p. 31 SMBus Connector (5-1 pins)
16) MSG.LED (PANEL) p. 32 System Message LED (2 pins)
17) SMI (PANEL) p. 32 SMI Switch Lead (2 pins)
18) PWR.SW (PANEL) p. 32 ATX Power & Soft-Off Switch Lead (2 pins)
19) RESET (PANEL) p. 32 Reset Switch Lead (2 pins)
20)
PWR.LED ( PANEL ) p. 32 System Power LED Lead (3 pins)
21)
KEYLOCK ( PANEL ) p. 32 Keyboard Lock Switch Lead (2 pins)
22) SPEAKER (PANEL) p. 32 Speaker Output Connector (4 pins)
*
The onboard hardware monitor uses the address 290H-297H so legacy ISA cards must not
use this address otherwise conflicts will occur.
Board Layout
III. H/W SETUP

ASUS P2B User’s Manual12
III. HARDWARE SETUP
Jumpers
III. H/W SETUP
Installation Steps
Before using your computer, you must complete the following steps:
1. Set Jumpers
2. Install Memory Modules
3. Install the Central Processing Unit (CPU)
4. Install Expansion Cards
5. Connect Ribbon Cables, Cabinet Wires, and Power Supply
6. Setup the BIOS Software
Jumpers
WARNING! Computer motherboards and expansion cards contain very delicate
Integrated Circuit (IC) chips. To protect them against damage from static electric-
ity, you should follow some precautions whenever you work on your computer.
1. Unplug your computer when working on the inside.
2. Use a grounded wrist strap before handling computer components. If you do
not have one, touch both of your hands to a safely grounded object or to a
metal object, such as the power supply case.
3. Hold components by the edges and try not to touch the IC chips, leads or
connectors, or other components.
4. Place components on a grounded antistatic pad or on the bag that came with
the component whenever the components are separated from the system.

ASUS P2B User’s Manual 13
III. HARDWARE SETUP
III. H/W SETUP
Jumpers
Jumper Settings
1. Clear Real Time Clock (RTC) RAM (CLRTC)
The CMOS RAM is powered by the onboard button cell battery. To clear the
RTC data: (1) Turn off your computer and unplug yourAC power, (2) Short the
two points labeled CLRTC, (3) Turn on your computer, (4) Hold down
<Delete> during bootup and enter BIOS setup to re-enter user preferences.
Short small solder points to clear CMOS
P2B Clear RTC RAM
CLRTC
R
2. Keyboard Power Up (KBPWR)
This allows you to disable or enable the keyboard power up function. Set to
Enable if you want to use your keyboard (by pressing <Spacebar>) to power up
your computer. This feature requires an ATX power supply that can supply at
least 300mAon the +5VSB lead and the newACPI BIOS support.The default is
set to Disable because not all computers have the appropriate ATX power sup-
ply. Your computer will not function if you set this to Enable and if you do not
have the right ATX power supply.
R
Disable
123KBPWR
Enable
123
P2B Keyboard Power Up

ASUS P2B User’s Manual14
III. HARDWARE SETUP
Jumpers
III. H/W SETUP
3. CPU Bus Frequency (FS0, FS1, FS2)
This option tells the clock generator what frequency to send to the CPU, DRAM, and
AGPset. This allows the selection of the CPU’s External frequency (or BUS Clock).
The BUS Clock multiplied by the BUS Ratio equals the CPU’s Internal frequency (the
advertised CPU speed).
4. CPU Core:BUS Frequency Multiple (BF0, BF1, BF2, BF3)
This option sets the frequency ratio between the Internal frequency of the CPU
and the CPU’s External frequency. These must be set in conjunction with the CPU
Bus Frequency.
BF2
BF1
BF3
CPU Core:BUS Frequency Multiple
P2B CPU
R
BF0
BF2
BF1
BF3
BF0
BF2
BF1
BF3
BF0
BF2
BF1
BF3
BF0
BF2
BF1
BF3
BF0
BF2
BF1
BF3
BF0
BF2
BF1
BF3
BF0
2.0x (2/1) 2.5x (5/2) 3.0X (3/1) 3.5X (7/2) 4.0X (4/1) 4.5X (9/2) 5.0X (5/1)
FS1 FS2 FS0
1
2
3
FS1 FS2 FS0
1
2
3
FS1 FS2 FS0
1
2
3
2
1
3
2
1
32
1
32
1
32
1
32
1
3
FS1 FS2 FS0
1
2
3
FS1 FS2 FS0
1
2
3
FS1 FS2 FS0
103MHz
33.4MHz
CPU External Clock (BUS) Frequency Selection
CPU
PCI
66.8MHz
33.4MHz 75MHz 37.5MHz 83.3MHz 41.65MHz 100.2MHz 33.3MHz 112MHz 37.3MHz
BF2
BF1
BF3
BF0
BF2
BF1
BF3
BF0
BF2
BF1
BF3
BF0
BF2
BF1
BF3
BF0
BF2
BF1
BF3
BF0
BF2
BF1
BF3
BF0
5.5x (11/2) 6.0x (6/1) 6.5X (13/2) 7.0X (7/1) 7.5X (15/2) 8.0X (8/1)
2
1
3
2
1
32
1
32
1
32
1
3
1
2
3
FS1 FS2 FS0
133MHz
33.3MHz/
44.3MHz
WARNING! Frequencies above 100MHz exceed the specifications for the on-
board Intel Chipset and are not guaranteed to be stable.

ASUS P2B User’s Manual 15
III. HARDWARE SETUP
III. H/W SETUP
Jumpers
Set the jumpers by the Internal speed of your processor as follows:
(BUS Freq.) (Freq. Ratio)
Intel CPU Model Freq. Ratio BUS F.FS0 FS1 FS2 BF0 BF1 BF2 BF3
Pentium III 550MHz 5.5x 100MHz [1-2] [1-2] [1-2] [1-2] [1-2] [1-2] [2-3]
Pentium III 500MHz 5.0x 100MHz [1-2] [1-2] [1-2] [2-3] [1-2] [1-2] [2-3]
Pentium III/II 450MHz 4.5x 100MHz [1-2] [1-2] [1-2] [1-2] [2-3] [1-2] [2-3]
Pentium II 400MHz 4.0x 100MHz [1-2] [1-2] [1-2] [2-3] [2-3] [1-2] [2-3]
Pentium II 350MHz 3.5x 100MHz [1-2] [1-2] [1-2] [1-2] [1-2] [2-3] [2-3]
Celeron 466MHz 7.0x 66MHz [1-2] [1-2] [2-3] [2-3] [1-2] [2-3] [1-2]
Celeron 433MHz 6.5x 66MHz [1-2] [1-2] [2-3] [1-2] [2-3] [2-3] [1-2]
Celeron 400MHz 6.0x 66MHz [1-2] [1-2] [2-3] [2-3] [2-3] [2-3] [1-2]
Pentium II/Celeron 333MHz 5.0x 66MHz [1-2] [1-2] [2-3] [2-3] [1-2] [1-2] [2-3]
Pentium II/Celeron 300MHz 4.5x 66MHz [1-2] [1-2] [2-3] [1-2] [2-3] [1-2] [2-3]
Pentium II/Celeron 266MHz 4.0x 66MHz [1-2] [1-2] [2-3] [2-3] [2-3] [1-2] [2-3]
Pentium II 233MHz 3.5x 66MHz [1-2] [1-2] [2-3] [1-2] [1-2] [2-3] [2-3]
For updated processor settings, please visitASUS’web site (seeASUS CONTACT INFORMATION)
NOTES:Overclocking your processor is not recommended. It may result in a slower
speed. Voltage Regulator Output Selection (VID) is not needed for the Pentium III/
II/Celeron processor because it sends a VID signal directly to the onboard power
controller.

ASUS P2B User’s Manual16
(This page was intentionally left blank.)
III. HARDWARE SETUP
Jumpers
III. H/W SETUP

ASUS P2B User’s Manual 17
III. H/W SETUP
System Memory
Install memory in any combination as follows:
DIMM Location 168-pin DIMM Total Memory
Socket 1 (Rows 0&1) SDRAM 8, 16, 32, 64, 128, 256MB x1
Socket 2 (Rows 2&3) SDRAM 8, 16, 32, 64, 128, 256MB x1
Socket 3 (Rows 4&5) SDRAM 8, 16, 32, 64, 128, 256MB x1
Total System Memory (Max 768MB) =
III. HARDWARE SETUP
System Memory (DIMM)
NOTE: No hardware or BIOS setup is required after adding or removing memory.
This motherboard uses only Dual Inline Memory Modules (DIMMs). Sockets are
available for 3.3Volt (power level) unbuffered Synchronous Dynamic Random Ac-
cess Memory (SDRAM). One side (with memory chips) of the DIMM takes up one
row on the motherboard.
To utilize the chipset’s Error Checking and Correction (ECC) feature, you must use a
DIMM module with 9 chips per side (standard 8 chips/side + 1 ECC chip) and make
the proper settings through Chipset Features Setup in BIOS SETUP.
MemoryspeedsetupisrecommendedthroughSDRAM Configuration under “Chipset
Features Setup” in BIOS SETUP.
NOTE: At the time this User’s Manual was written, 256MB DIMMs are only avail-
able as registered memory.
SPD Support
This motherboard supports SPD DIMMs, and it is recommended that SPD DIMMs
be used.
General DIMM Notes
•Forthe systemCPU bus to operate above 100MHz, use only PC100-compli-
ant DIMMs. When this motherboard operates at 100MHz, most system will not
even boot if non-compliant modules are used because of the strict timing issues
involved under this speed. If your DIMMs are not PC100-compliant, set the
CPU bus frequency (FS) to 66MHz for system stability.
• ASUS motherboards support SPD (Serial Presence Detect) DIMMs. This is the
memory of choice for best performance vs. stability.
• SDRAM chips are generally thinner with higher pin density than EDO (Ex-
tended Data Output) chips.
• BIOS shows SDRAM memory on bootup screen.
• Single-sidedDIMMscomein16,32,64,128MB;double-sidedcomein32,64,128,256MB.

ASUS P2B User’s Manual18
System Memory
III. H/W SETUP
III. HARDWARE SETUP
DIMM Memory Installation Procedures:
Insert the module(s) as shown. Because the number of pins are different on either
side of the breaks, the module will only fit in the orientation as shown. DRAM
SIMM modules have the same pin contacts on both sides. SDRAM DIMMs have
different pin contacts on each side and therefore have a higher pin density.
Lock
P2B 168-Pin DIMM Memory Sockets
20 Pins 60 Pins 88 Pins
R
FRONT
The DIMMs must be 3.3Volt unbuffered SDRAMs. To determine the DIMM type,
check the notches on the DIMMs (see figure below).
The notches on the DIMM will shift between left, center, or right to identify the type
and also to prevent the wrong type from being inserted into the DIMM slot on the
motherboard. You must tell your retailer the correct DIMM type before purchasing.
This motherboard supports four clock signals.
168-Pin DIMM Notch Key Definitions (3.3V)
DRAM Key Position Voltage Key Position
Unbuffered
RFU
Buffered Reserved
3.3V
5.0V

ASUS P2B User’s Manual 19
III. HARDWARE SETUP
CPU
III.H/WSETUP
Central Processing Unit (CPU)
NOTE: The following pictures are provided for reference purposes only. The ap-
pearance of your retention mechanism and fan may be different from the following
examples.
Your motherboard provides a Slot 1 connector for a Pentium
®
III processor pack-
aged in a Single Edge Contact Cartridge (SECC2), a Pentium
®
II processor pack-
aged in SECC/SECC2, or a Celeron™ processor packaged in a Single Edge Proces-
sor Package (SEPP). An ASUS S370 CPU card can allow Socket 370 processors to
be used on anyASUS motherboard with the Slot 1 connector (See ASUS S370 CPU
Card inAPPENDIX for instructions on using this card).
Heatsinks
The recommended heatsinks (see section on recommended heatsinks for Pentium
III / II processors for more information) for the boxed Pentium III / II and Celeron
processors are those with three-pin fans that can be connected to the fan connectors
on the motherboard.
WARNING! Be sure that there is sufficient air circulation across the processor’s
heatsink by regularly checking that your CPU fan is working. Without sufficient
circulation, the processor could overheat and damage both the processor and the
motherboard. You may install an auxiliary chassis fan, if necessary.
Pentium II processor packaged in an SECC with
heatsink and fan (top view) Pentium III (in an SECC2) with heatsink and fan NOTE: The SEPP fan (for Celeron processors) is
similar to SECC2 fan except that the clamping
design is different.
Your motherboard comes preinstalled
with a Universal Retention Mechanism
(URM). The URM supports Pentium III /
II and Celeron processors.
Universal Retention Mechanism (URM)
Universal Retention Mechanism

20 ASUS P2B User’s Manual
III. HARDWARE SETUP
CPU
III.H/WSETUP
2. Attach the Heatsink
NOTE: If provided, you should follow the heatsink attachment instructions
that came with your heatsink or processor. The following steps are provided
only as a general guide and may not reflect those for your heatsink.
The URM is now ready for the installation
of your processor.
Installing the Processor
1. UnlocktheURM’sFolding SupportArms:
The folding support arms of the URM are
locked when shipped.
Using the SECC fan with the Pentium
®
II
Pushthetwolock arms one directiontoclamp
the heatsink onto the processor and the other
direction to release.
UsingtheSECC2fanwiththePentium
®
III
Insert the four heatsink’s pins through the
holes of the SECC2. Place the metal clip on
the ends of the pins and slide until it locks
into place.
Unlocked Folding
SupportArms
Locked Folding
SupportArms
To unlock the support arms, simply flip them
up to an upright position.
LockArm LockArm
Four Pins and metal clip
NOTE: The SEPP heatsink and fan (for Intel Celeron processors) is similar to
the SECC2 heatsink and fan except that the clamping design is different.