Asus P2B-N User manual

R
P2B-N
Pentium®II NLX Motherboard
USER’S MANUAL

2ASUS P2B-N User’s Manual
USER’S NOTICE
Product Name: ASUS P2B-N
Manual Revision: 1.03 (E291)
Release Date: November 1998
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.
• Sound Blaster AWE32 and SB16 are trademarks of Creative Technology Ltd.
• 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 MANUALARE 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
ANYERRORSORINACCURACIESTHATMAYAPPEARINTHIS MANUAL, INCLUD-
ING THE PRODUCTSAND SOFTWARE DESCRIBED IN IT.
Copyright © 1998 ASUSTeK COMPUTER INC. All Rights Reserved.

ASUS P2B-N User’s Manual 3
ASUS CONTACT INFORMATION
ASUSTeK COMPUTER INC.
Marketing
Address: 150 Li-Te Road, Peitou, Taipei, Taiwan 112
Telephone: [phone]
Fax: [phone]
Email: [email protected]
Technical Support
Fax: [phone]
BBS: [phone]
Email: [email protected]
WWW: www.asus.com.tw
FTP: ftp.asus.com.tw/pub/ASUS
ASUS COMPUTER INTERNATIONAL
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
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-N User’s Manual
CONTENTS
I. INTRODUCTION.............................................................................. 7
How this manual is organized............................................................. 7
Item Checklist ..................................................................................... 7
II. FEATURES ....................................................................................... 8
Features of the ASUS P2B-N Motherboard........................................ 8
Parts of the ASUS P2B-N Motherboard...................................... 11
Riser Card Back .......................................................................... 11
Riser Card Front .......................................................................... 11
III. INSTALLATION ........................................................................... 12
ASUS P2B-N Motherboard Layout .................................................. 12
Installation Steps............................................................................... 14
1. Jumpers ......................................................................................... 14
2. System Memory (DIMM) ............................................................. 19
DIMM Memory Installation .................................................. 20
3. Central Processing Unit (CPU).................................................... 21
Universal Retention Mechanism ........................................... 21
Heatsinks ............................................................................... 21
Installing the Processor ............................................................... 22
ASUS Smart Thermal Solutions............................................ 24
Recommended Heatsinks for Slot 1 Processors .................... 25
4. Expansion Cards ........................................................................... 26
Expansion Card Installation Procedure ................................. 26
Assigning IRQs for Expansion Cards.................................... 26
Assigning DMA Channels for ISA Cards.............................. 27
ISA Cards and Hardware Monitor ......................................... 27
5. External Connectors..................................................................... 28
Front Panel Descriptions ............................................................. 33
Power Connection Procedures .......................................................... 37
Flash Memory Writer Utility ............................................................ 38
IV. BIOS SOFTWARE ......................................................................... 38
Main Menu .................................................................................. 38
Managing and Updating Your Motherboard’s BIOS................... 40
6. BIOS Setup .................................................................................. 41
Load Defaults ........................................................................ 42
Standard CMOS Setup ................................................................ 42
Details of Standard CMOS Setup:......................................... 42
BIOS Features Setup ................................................................... 45
Details of BIOS Features Setup............................................. 45

ASUS P2B-N User’s Manual 5
CONTENTS
Chipset Features Setup ................................................................ 48
Details of Chipset Features Setup.......................................... 48
Power Management Setup........................................................... 51
Details of Power Management Setup .................................... 51
PNP and PCI Setup ..................................................................... 54
Details of PNP and PCI Setup ............................................... 54
Load BIOS Defaults .................................................................... 56
Load Setup Defaults .................................................................... 56
Supervisor Password and User Password ................................... 57
IDE HDD Auto Detection ........................................................... 58
Save & Exit Setup ....................................................................... 59
Exit Without Saving .................................................................... 59
V. SUPPORT CD ................................................................................. 61
ASUS Support CD Main Menu ........................................................ 61
A. ASUS Probe Setup ...................................................................... 65
B. Video Driver................................................................................ 71
Other Video Drivers .................................................................... 75
C. ATI Player ................................................................................... 85
D. Audio Driver ............................................................................... 89
E. Audio Software ........................................................................... 93
F. Software Wavetable................................................................... 102
G. Network Interface...................................................................... 103
H. DMI Utility................................................................................ 117

6ASUS P2B-N 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:
• 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.
WARNING! The use of shielded cables for connection of the monitor to the
graphics card is required to assure compliance with FCC regulations. Changes
or modifications to this unit not expressly approved by the party responsible for
compliance could void the user’s authority to operate this equipment.
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.

ASUS P2B-N 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. Installation: Instructions on setting up the motherboard and jumpers
IV. BIOS Software: Instructions on setting up the BIOS software
V. Support CD: Information on the included support software
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 one hard disk drive
(1) Floppy ribbon cable for one 3.5” floppy disk drive
(1) FPC slim CD-ROM cable
(1) Support CD with drivers and utilities
(1) Motherboard User’s Manual
(1) System housing User’s Manual
(1) NLX Form-factor system housing, riser card, and power supply
ASUS Slim CD-ROM (optional)
ASUS PC100-compliant SDRAM (optional)
S-P2FAN or P2T-Cable for Slot 1 processors (optional)
IrDA-compliant infrared module (optional)

8ASUS P2B-N User’s Manual
Features of theASUS P2B-N Motherboard
The ASUS P2B-N motherboard is carefully designed for the demanding PC user
who wants many advanced features processed by the fastest CPU.
Specifications
•NLX: Features ASUS’custom designed NLX form factor.
•Multi-Speed: Supports Intel Pentium
®
II (233MHz to 450MHz) and Celeron
TM
(266MHz and faster) processors.
•Multi-Cache:Supportsprocessors with orwithout Pipelined BurstLevel 2 cache.
•IntelAGPset:FeaturesIntel’s440BXAGPsetwithI/Osubsystemsand front-sidebus
(FSB) platform, which boosts the traditional 66-MHz internal bus speed to 100MHz.
•PC100 Memory Support: Equipped with two DIMM sockets to support Intel
PC100-compliant SDRAMs (8, 16, 32, 64, 128, or 256MB) up to 512MB.
•100/10Mbps LAN: Features an onboard Intel 82558 Ethernet LAN Controller
(fully integrated 10BASE-T/100BASE-TX) and a LANActivity LED for moni-
toring network conditions.
•AGPVGA: Features an onboard ATI 3D Rage ProAGP 2X (8MB SDRAM) or
Rage IIC (4MB SDRAM) for 3D hardware acceleration.
•PCI Audio: Features onboard the ESS Solo-1 32-bit 3D positional PCI audio
which supports games and applications for Sound Blaster
TM
and Sound Blaster
Pro and full-duplex stereo.
•ThermalSensorConnectorwithOptionalSensor:Accuratelydetects the CPU
temperature of processors with the ASUS Smart Fan or the Intel boxed proces-
sor heatsink with fan when connected to an ASUS P2T-Cable.
•Hardware Monitoring: Monitors your system’s vital components/activities,
such as fan rotations, voltages, and temperatures.
•Riser Card: Provides NLX power, primary IDE, floppy drive, LAN wake up
connector, 2 PCI slots, 1 ISA slot, 2 USB ports, and 1 IrDA port.
•Ultra DMA/33 BM IDE: Comes with an onboard PCI Bus Master IDE controller
with two connectors that supports four IDE devices in two channels, supports Ultra
DMA/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.
•Universal Retention 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).
•Wake-On-LAN Connector: Supports Wake-On-LAN activity through the net-
work interface.
•IrDA Port: Features an infrared port on the riser card for wireless interface.
•Slim CD-ROM: Supports an optional ASUS slim CD-ROM drive for ASUS’
custom designed NLX form factor.
II. FEATURES
Features
II. FEATURES

ASUS P2B-N User’s Manual 9
Special Features
• ACPI Ready: Features ACPI (Advanced Configuration and Power Interface)
which is implemented on all ASUS smart series motherboards. ACPI provides
more Energy Saving Features for future operating systems (OS) supporting OS
Direct Power Management (OSPM) functionality. With these features imple-
mented in the OS, PCs can be ready around the clock, yet satisfy all the energy
saving standards. To fully utilize the benefits of ACPI, an ACPI-supported OS
such as the successor of Windows 95 must be used.
• Desktop Management Interface (DMI): Supports DMI through BIOS which
allows hardware to communicate within a standard protocol creating a higher
level of compatibility. (Requires DMI-enabled components.)
•Easy Installation: Incorporates BIOS that supports autodetection of hard disk
drives, PS/2 mouse, and Plug and Play devices to make setup of hard disk drives,
expansion cards, and other devices virtually automatic.
•Enhanced ACPI & Anti-Boot Virus BIOS: Features a programmable BIOS
(Flash EEPROM), offering enhancedACPI forWindows 98 compatibility, built-
in hardware-based virus protection, and autodetection of most devices for virtu-
ally automatic setup.
• PC ’98 Compliant: Meets PC ’98 compliancy in both the BIOS and hardware
levels of ASUS smart series motherboards. The new PC ‘98 requirements for
systems and components are based on the following high-level goals: Support
for Plug and Play compatibility and power management for configuring and
managing all system components, and 32-bit device drivers and installation pro-
cedures for Windows 95/98/NT.
•BundledPC-cillin:Automaticallydetectsandremovesallviruseswhileyourwork.
Performance
•Concurrent PCI: Supports concurrent PCI, allowing multiple PCI transfers
from PCI master buses to memory to CPU.
• Double the IDE Transfer Speed: Supports Ultra DMA/33 Bus Master IDE,
which can imporve data transfers up to 33MB/s. The best of all is that this new
technology is compatible with existing ATA-2 IDE specs so there is no need to
upgrade current hard drives or cables.
• SDRAMOptimized Performance: Supports the new generation memory, Syn-
chronous Dynamic Random Access Memory (SDRAM), which increases the
data transfer rate from 264MB/s max (using EDO memory) to 528MB/s max
(using SDRAM).
II. FEATURES
Features
II. FEATURES

10 ASUS P2B-N User’s Manual
Intelligence:
• Auto Fan Off: The system fans will power off automatically even in sleep
mode. This function reduces both energy consumption and system noise, and
is a important feature to implement silent PC systems.
• Boot Virus Protection:Anti-boot virus protection programmed into the BIOS.
• Dual Function Power Button: Pushing the power button for less than 4 sec-
onds when the system is in the working state places the system into one of two
states: sleep mode or soft-off mode, depending on the BIOS setting (see “Power
Management Setup” in IV. BIOS SOFTWARE). When the power button is
pressed for more than 4 seconds, it enters the soft-off mode regardless of the
BIOS setting.
• Fan Status Monitoring and Alarm: To prevent system overheat and system
damage, the CPU fan and system fans can be monitored for RPM and failure.
All fans are set for its normal RPM range and alarm thresholds.
• Keyboard Power (Wake) Up: Keyboard Power (Wake) Up can be enabled or
disabled to allow the computer to be powered on from the keyboard.
• Message LED (requires ACPI OS support): Chassis LEDs now act as infor-
mation providers. Through the way a particular LED illuminates, the user can
determine the stage the computer is in.A simple glimpse provides useful infor-
mation to the user.
• Remote Ring On (requires external modem): This allows a computer to be
turned on remotely through an external modem. With this benefit on-hand, any
usercanaccess vital informationfrom their computer fromanywhere in theworld!
• SystemResourcesAlert:Today’s operating systems such as Windows 95, Win-
dows NT, and OS/2, require much more memory and hard drive space to present
enormous user interfaces and run large applications. The system resource moni-
tor will warn the user before the system resources are used up to prevent pos-
sible application crashes. Suggestions will give the user information on manag-
ing their limited resources more efficiently.
•Temperature Monitoring and Alert: To prevent system overheat and system
damage, there are thermal sensors to monitor the CPU (the Pentium II processor
requires a special heatsink with a thermal sensor) and system temperatures to
warn of damaging temperatures.
•Voltage Monitoring and Alert: System voltage levels are monitored to ensure
stable current to critical motherboard components. Voltage specifications are
more critical for future processors, so monitoring is necessary to ensure proper
system configuration and management.
II. FEATURES
Features
II. FEATURES

ASUS P2B-N User’s Manual 11
Parts of the ASUS P2B-N Motherboard
II. FEATURES
II. FEATURES
Motherboard Parts
2 PCI Slots
1ISASlot Floppy Drive
Connector
Riser Card Front
NLX Slot
ATI 3D Rage Pro
AGP 2X/Rage IIC
VGAChipset
Keyboard BIOS,
Multi-I/O
T: PS/2 Mouse
B: PS/2 Keyboard
T: Parallel Conn.
B: Serial Conn. COM 2
Programmable
Flash EEPROM
Intel 440BXAGPset
Intel PIIX4E PCIset
2 DIMM Sockets
COM 1 VGAConnector Joystick/MIDI
ConnectorLAN LED
RJ-45
4MB (Rage IIC)/
8MB (Rage Pro)
VGAMemory
Slim CD-ROM Connector
CPU Slot 1
Universal Folding
Retention Mechanism
Onboard ESSAudio
Intel 82558
LAN Controller
2 USB Ports
IrDAPort Primary IDE
Connector
NLX Power
Connector
Riser Card Back
Golden Finger
Connector
H/W MonitoringASIC
ASUSASIC

12 ASUS P2B-N User’s Manual
III. INSTALLATION
ASUS P2B-N Motherboard Layout
Motherboard Layout
III. INSTALLATION
Floppy Drive Conn.
PCI Slot 2
PCI Slot 1
ISA Slot 1
Panel Conn.
NLX Ext. Riser Slot Riser Slot Riser Slot
LAN LED Wake on LAN
MIC Con.
Riser Card Front
Primary IDE
NLX Power
USB1&2
Infrared
Riser Card Back
RJ-45
PS/2
Parallel
Port
Connector
COM 1 COM 2 Joystick/MIDI
CPU Slot 1
Intel
440BX
AGPset
Intel
PIIX4E
Chipset
ATI 3D Rage
Pro AGP 2X/
Rage IIC
VGA
Chipset
ASUS
ASIC
Keyboard
BIOS, RTC,
& Multi-I/O
CDROM Connector
32-bit
PCI
Audio
Hardware
Monitor
Intel 82558
Ethernet
LAN
Controller
GAME
SDRAM
SDRAM SDRAM
Rage Pro VGA: 8MB SDRAM
Rage IIC VGA: 4MB SDRAM
CLR_RTC
FREQ MULT
BF0 BF1 BF2 BF3
R
TOP:
MOUSE
BOTTOM:
KEYBOARD
VGA
Flash EEPROM
(Programmable BIOS)
CMOS
Power
CR2032
3 Volt Cell
DIMM Socket 2 (64/72-bit, 168-pin module)
DIMM Socket 1 (64/72-bit, 168-pin module)
32 10Row
CPU_FAN
1
FS1
FS0
BUS FREQ SELECT
FS2
JACK_CON
1
CHASIS_FAN
AMC
CPU THEM
LAN_LED
SDRAM
LANDIS_EN
VIO
AUDIS_EN
MODEM
KB_WAKE

ASUS P2B-N User’s Manual 13
III. INSTALLATION
Jumpers
1) CLR_RTC P. 14 Real Time Clock (RTC) RAM
2) VIO p. 15 Voltage Input/Output Selection
3) LANDIS_EN p. 15 LAN Setting (Enable/Disable)
4) AUDIS_EN p. 15 Audio Setting (Enable/Disable)
5) KB_WAKE p. 16 Keyboard Wake Up (Enable/Disable)
6) FS0, FS1, FS2 p. 16 CPU External Clock (BUS) Frequency Selection
7) BF0, BF1, BF2, BF3 p. 17 CPU Core:BUS Frequency Multiple
Expansion Slots
1) DIMM Sockets p. 19 168-pin DIMM Memory Expansion Sockets
2) CPU Slot 1 p. 21 Pentium
®
II/Celeron™ CPU Support
3) SLOT 1 (ISA)* p. 26 16-bit ISA Bus Expansion Slots*
4) PCI1, 2 p. 26 32-bit PCI Bus Expansion Slots
Hardware Monitor
1) CPU THEM p. 25 Pentium II/Celeron Processor Thermal Sensor Connector
Connectors
1) PS2KBMS p. 28 PS/2 Mouse Connector (6-pin female)
2) PS2KBMS p. 28 PS/2 Keyboard Connector (6-pin female)
3) GAME p. 28 Joystick or MIDI Connector (15-pin female)
4) PRINTER p. 29 Parallel Port Connector (25-pin female)
5) COM1, COM2 p. 29 Serial Port COM1 and COM2 (Two 9-pin male)
6) VGA p. 29 VGA Compatible Connector (15-pin female)
7) LAN_LED p. 29 LAN Diagnostic LEDs
8) USB p. 30 Universal Serial BUS Ports 1 & 2 (Two 4-pin female)
9) IR p. 30 Infrared Module
10) NLX_PWR p. 30 NLX Motherboard Power Connector (20-pin block)
11) IDE1 p. 31 Primary IDE Connector (40-pin block)
12) FLOPPY p. 31 Floppy Drive Connector (34-pin block)
13) LAN_LED,WOL_CON p. 31 LAN Activity Connectors (2-pin & 3-pin)
14) PAN-CON p. 32 Front Panel Display LEDs and Switches (16-1 pin)
15) MIC-CON p. 32 Front Panel Microphone Jack Connector (2-pin)
16) AMC p. 34 ATI Multimedia Connector (40-3 pin block)
17) JACK_CON p. 34 Back Panel Audio Connectors (10-1 pin block)
18) CPU_, CHASIS_FAN p. 34 CPU Fan Power (Two 3-pin blocks)
19) CDROM p. 35 CD-ROM Drive Connector (50-3 pins)
*
The onboard hardware monitor uses the address 290H-297H so legacy ISA cards
must not use this address or else conflicts will occur.
Map of Board
III. INSTALLATION

14 ASUS P2B-N User’s Manual
Jumpers
III. INSTALLATION
1. Jumpers
1. Real Time Clock (RTC) RAM (CLR_RTC)
The CMOS RAM is powered by the onboard button cell battery. To clear the
RTC data: (1) Unplug your computer, (2) Short solder points, (3) Turn on your
computer, (4) Hold down <Delete> during bootup and enter BIOS setup to re-
enter user preferences.
P2B-N Clear RTC RAM
R
CLR_RTC
Short solder points
to clear CMOS
WARNING!Computer motherboards, baseboards and components,such asSCSI
cards, contain very delicate Integrated Circuit (IC) chips. To protect them against
damage from static electricity, 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.
III. INSTALLATION
Installation Steps
Before using your computer, you must complete the following steps:
1. Set Jumpers on the Motherboard (if necessary)
2. Install System 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

ASUS P2B-N User’s Manual 15
2. +3V Voltage Selection (VIO)
This jumper allows you to select the voltage supplied to the DRAM, chipset,
AGP, and the CPU’s I/O buffer. IMPORTANT! Setting this jumper to High
Volt (3.5V) may cause your system to become unstable. It is strongly recom-
mended that you leave this jumper on its default setting of Normal Volt (3.3V).
P2B-N Voltage Input/Output Selection
VIO
High
Voltage
3
2
1
Normal
Voltage
(default)
3
2
1
VIO
R
3. LAN Setting (LANDIS_EN)
The onboard Intel 10/100 Fast Ethernet may be enabled or disabled using this
jumper. The default is set to Enable.
P2B-N Onboard LAN Setting
LANDIS_EN
Enable
3
2
1
Disable
(Default)
3
2
1
LANDIS_EN
R
4. Audio Setting (AUDIS_EN)
The onboard 32-bit PCI audio may be enabled or disabled using this jumper.
P2B-N Onboard Audio Setting
R
Enable
(Default)
321
AUDIS_EN
321
AUDIS_EN
Disable
III. INSTALLATION
AUDIS EN Setting
Enable [2-3] (default)
Disable [1-2]
VIO Setting
Normal Volt [2-3] (default)
High Volt [1-2]
LANDIS EN Setting
Enable [2-3] (default)
Disable [1-2]
Jumpers
III. INSTALLATION

16 ASUS P2B-N User’s Manual
Jumpers
III. INSTALLATION
III. INSTALLATION
5. Keyboard Wake Up (KB_WAKE)
This allows you to disable or enable the keyboard power up function. Set this
jumper to Enable if you wish to use your keyboard (by pressing the spacebar) to
power up your computer. This feature requires an ATX power supply that can
supply at least 300mAmp on the +5VSB lead. The default is set to Disable
because not all computers have the appropriate ATX power supply. Your com-
puter will not power on if you set this to Enable and if you do not have the right
ATX power supply. WARNING! This jumper setting must coincide with the
BIOS setting (see “Power Up By Keyboard” in the Power Management Setup of
the BIOS SOFTWARE) or else conflicts will occur.
P2B-N Keyboard Wake Up
KB_WAKE
Disable
(Default)
321
Enable
321
KB_WAKE
R
6. CPU Bus Frequency Selector (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).
P2B-N CPU Bus Frequency Setting
R
321
66.8MHZ
33.1MHZ
321
75.0MHZ
37.5MHZ
321
83.3MHZ
41.7MHZ
321
100.2MHZ
33.3MHZ
321
112.0MHZ
37.3MHZ
321
103.0MHZ
33.4MHZ
321
133.0MHZ
33.3MHZ
PCI
CPU
→
→
→
→
→
FS1
FS2
FS0
PCI
CPU
→
→
→
→
→
FS1
FS2
FS0
KB WAKE Setting
Disable [1-2] (default)
Enable [2-3]

ASUS P2B-N User’s Manual 17
7. CPU Core:BUS Frequency Multiple (BF0, BF1, BF2, BF3)
This option sets the frequency multiple between the Internal frequency of the
CPU and the CPU’s External frequency. These must be set in conjunction with the
CPU Bus Frequency.
P2B-N CPU Core:Bus Frequency Multiple Selection
R
2.5x(5/2)
4.0x(4/1) 4.5x(9/2) 5.0x(5/1)
2.0x(2/1)
3
2
1
BF1 BF2 BF0 BF3
BF1 BF2 BF0 BF3
BF1 BF2 BF0 BF3
BF1 BF2 BF0 BF3 BF1 BF2 BF0 BF3
3
2
1
3.5x(7/2)3.0x(3/1)
BF1 BF2 BF0 BF3 BF1 BF2 BF0 BF3
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 II
processor because it sends a VID signal directly to the onboard power controller.
Set the jumpers by the Internal speed of your processor asfollows:
(CPU BUS Freq.) (Freq. Multiple)
Intel CPU Model Freq. Ratio BUS F. FS0 FS1 FS2 BF0 BF1 BF2 BF3
Pentium 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]
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]
WARNING! Frequencies above 100MHz exceed the specifications for the on-
board Intel Chipset and are not guaranteed to be stable.
WARNING! PCI frequencies above 33MHz exceed the specifications for PCI
cards and are not guaranteed to be stable.
III. INSTALLATION
Jumpers
III. INSTALLATION

18 ASUS P2B-N User’s Manual
III. INSTALLATION
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ASUS P2B-N User’s Manual 19
III. INSTALLATION
System Memory
III. INSTALLATION
Install memory in any combination as follows:
DIMM Location 168-pin DIMM Memory Modules 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
Total System Memory (Max 512MB) =
2. System Memory (DIMM)
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.
Memoryspeed setup is recommended throughSDRAM Configuration under “Chipset
Features Setup” in BIOS setup.
General DIMM Notes
•For the system CPU bus to operate at 100MHz, use only PC100-compliant
DIMMs compatible with Intel’s PC100 SDRAM specifications. This
motherboard operates at 100MHz, thus most systems 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
to 66MHz.
• Two possible memory chips are supported: SDRAM with and without ECC.
• SDRAM chips are generally thinner with higher pin density than EDO (Ex-
tended Data Output) chips.
• BIOS shows SDRAM memory on bootup screen.
• 8chips/sidemodules do not supportECC,only 9 chips/side modulessupportECC.
• Single-sidedDIMMscomein16,32,64,128MB;double-sidedcomein32,64,128,256MB.

20 ASUS P2B-N User’s Manual
III. INSTALLATION
System Memory
III. INSTALLATION
DIMM Memory Installation
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. DIMM
modules are longer and have different pin contact on each side and therefore have a
higher pin density. SIMM modules have the same pin contact on both sides.
P2B-N 168-pin DIMM Memory Sockets
Lock
R
20 Pins
88 Pins 60 Pins
The Dual Inline Memory Module (DIMM) must be 3.3VUnbuffered for this moth-
erboard. You can identify the type of DIMM module by the illustration below:
168-Pin DIMM Notch Key Definitions (3.3V)
DRAM Key Position Voltage Key Position
Unbuffered
RFU
Buffered Reserved
3.3V
5.0V
The notch on the DIMM module will shift between left, center, or right to identify the
type and also to prevent the wrong type of DIMM to be inserted into the DIMM socket
on the motherboard. Four clock signals are supported on this motherboard. You must
ask your retailer for the specifications before purchasing memory modules.