User manual ASUS CP6ND

R C-P6ND CPU Card USER'S MANUAL USER'S NOTICE No part of this product, including the product and software may be reproduced, transmitted, transcribed, stored in a retrieval system, or translated into any language in any form by any means without the express written permission of ASUSTeK COMPUTER INC. (hereinafter referred to as ASUS) except documentation kept by the purchaser for backup purposes. 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 be liable for any loss or profits, loss of business, loss of use or data, interruption of business, or for indirect, special, incidental, or consequential damages of any kind, even if ASUS has been advised of the possibility of such damages arising from any defect or error in this manual or product. ASUS may revise this manual from time to time without notice. Products mentioned in this manual are mentioned for identification purposes only. Product names appearing in this manual may or may not be registered trademarks or copyrights of their respective companies. The product name and revision number are both printed on the board itself. Manual revisions are released for each board 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 updated BIOS, drivers, or product release information you may visit ASUS' home page at: http://www.asus.com.tw/ © Copyright 1996 ASUSTeK COMPUTER INC. All rights reserved. Product Name: C-P6ND Manual Revision: 1.21 Release Date: October 1996 II ASUS C-P6ND User's Manual ASUS CONTACT INFORMATION ASUSTeK COMPUTER INC. Marketing Info: Address: 150 Li-Te Road, Peitou, Taipei, Taiwan, ROC Telephone: 886-2-894-3447 Fax: 886-2-894-3449 Email: info@asus.com.tw Technical Support: Fax: BBS: Email: WWW: Gopher: FTP: 886-2-895-9254 886-2-896-4667 tsd@asus.com.tw http://www.asus.com.tw/ gopher.asus.com.tw ftp.asus.com.tw/pub/ASUS ASUS COMPUTER INTERNATIONAL Marketing Info: Address: 721 Charcot Avenue, San Jose, CA 95131, USA Telephone: 1-408-474-0567 Fax: 1-408-474-0568 Email: info-usa@asus.com.tw Technical Support: BBS: Email: 1-408-474-0555 tsd-usa@asus.com.tw ASUS COMPUTER GmbH Marketing Info: Address: Harkort Str. 25, 40880 Ratingen, BRD, Germany Telephone: 49-2102-445011 Fax: 49-2102-442066 Email: info-ger@asus.com.tw Technical Support: BBS: Email: 49-2102-448690 tsd-ger@asus.com.tw ASUS C-P6ND User's Manual III CONTENTS I. INTRODUCTION ........................................................ 1 How this manual is organized .......................................................... 1 Item Checklist .................................................................................. 1 Features of the ASUS CPU Card ..................................................... 2 II. FEATURES ................................................................. 2 Map of the ASUS CPU Card ...................................................... 2 III. INSTALLATION ...................................................... 3 Jumper Settings .......................................................................... 3 Software BIOS ........................................................................... 5 Power Connection Procedures ................................................... 5 IV. BIOS SOFTWARE .................................................... 6 Support Software ............................................................................. 6 Flash Memory Writer Utility ........................................................... 6 Main Menu ........................................................................... 6 Advanced Features Menu ..................................................... 7 Updating your Motherboard's BIOS .......................................... 8 BIOS Setup ...................................................................................... 9 Load Defaults ..................................................................... 10 Standard CMOS Setup ............................................................. 10 Details of Standard CMOS Setup: ...................................... 11 BIOS Features Setup ................................................................ 14 Details of BIOS Features Setup: ......................................... 14 Chipset Features Setup ............................................................. 17 Power Management Setup ........................................................ 20 Details of Power Management Setup: ................................ 20 PNP and PCI Setup .................................................................. 22 Load BIOS Defaults ................................................................. 24 Load Setup Defaults ................................................................. 24 Supervisor Password and User Password ................................ 25 IDE HDD Auto Detection ........................................................ 26 Save and Exit Setup ................................................................. 27 Exit Without Saving ................................................................. 27 IV ASUS C-P6ND User's Manual CONTENTS V. DESKTOP MANAGEMENT ................................... 29 Desktop Management Interface (DMI) .......................................... 29 Introducing the ASUS DMI Configuration Utility ............. 29 System Requirements ......................................................... 29 Using the ASUS DMI Configuration Utility ...................... 30 Notes: .................................................................................. 30 ASUS C-P6ND User's Manual V FCC & DOC COMPLIANCE Federal Communications 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 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: · · · · 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: 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. 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. VI ASUS C-P6ND User's Manual I. INTRODUCTION This manual is divided into the following sections: I. II. III. IV. V. Introduction: Manual information and checklist Features: Information and specifications concerning this product Installation: Instructions on setting up the ASUS CPU card BIOS Setup: BIOS software setup information DMI Utility: BIOS supported Desktop Management Interface I. INTRODUCTION (Manual / Checklist) 1 How this manual is organized Item Checklist Please check that your package is complete. If you discover damaged or missing items, please contact your retailer. The ASUS C-P6ND CPU Card Support drivers and utilities as follows (view FILELIST.TXT for details) · Flash Memory Writer utility to update the FLASH BIOS · Desktop Management Interface (DMI) utility · Bus Master IDE Drivers · Readme files for descriptions and use of the files · Technical Support Form This user's manual ASUS C-P6ND User's Manual II. FEATURES Features of the ASUS CPU Card The ASUS C-P6ND is carefully designed for the demanding PC user who wants great versatility in the assembly of a computer system. This CPU card: · · · · · II. FEATURES (Features) 2 PS/2 Connectors: PS/2 Mouse & PS/2 Keyboard connectors on bracket. Versatile Processor Support: Supports dual 150-200MHz Pentium Pro Processor in ZIF socket 8. Intel Chipset: Features Intel's 440FX PCIset with I/O subsystems. Error Checking and Correcting (ECC): Using Intel's 440FX PCIset and parity DRAM modules can detect and correct 1 bit memory errors. Internal L2 Cache Support: Supports Intel CPU's built-in 256KB/512KB (depending on CPU) Level 2 cache so that no external SRAM chips are needed. Switching Voltage Regulators Switching Voltage Regulators Dual ZIF Socket 8 PS/2 Mouse PS/2 Keyboard Intel 440FX PCIset Map of the ASUS CPU Card ZIF Socket 8 ZIF Socket 8 PS/2 Mouse Processor 2 BUS Freq. JP6 JP7 Processor 1 PS/2 Keyboard VID Support (CPU 2) Fan Pwr Freq. Ratio Fan Pwr VID Support (CPU 1) ASUS C-P6ND User's Manual III. INSTALLATION Jumper Settings 1. CPU to BUS Frequency Ratio (JP13, 14, 15, 16) These jumpers set the frequency ratio between the Internal frequency of the CPU and the External frequency (called the BUS Clock) within the CPU. These must be set together with the above jumpers CPU External (BUS) Frequency Selection. 2. CPU External (BUS) Frequency Selection (JP6, 7) These jumpers tells the chipset what frequency the CPU is using. J P1 3 CPU : BUS Frequency Ratio (2.0x, 2.5x, 3.0x, 3.5x, 4.0x) Both processors must use the same settings. CPU External Clock (Chipset) Frequency Selection for 440FX PCIset (BUS Freq. Selection on baseboard) JP6 JP7 66MHz JP6 JP7 60MHz You must also the the CPU External Frequency on the baseboard as follows: 1 2 3 66MHz 1 2 3 60MHz CPU External Clock (BUS) Frequency Selection Set the jumpers by the Internal speed of the Intel Pentium Pro CPU as follows: (Chipset Freq) (CPU Card) JP6 JP7 [ON] [OFF] [OFF] [ON] [ON] [OFF] [OFF] [ON] (CPU Ext. Freq) (Baseboard) JP3 JP2 [1-2] [2-3] [2-3] [1-2] [1-2] [2-3] [2-3] [1-2] CPU Internal 200MHz 180MHz 166MHz 150MHz BUS Ratio 3.0x 3.0x 2.5x 2.5x (CPU Card BUS Ratio) JP13 JP14 JP15 JP16 [ON] [ON] [OFF] [ON] [ON] [ON] [OFF] [ON] Ext. Freq. 66MHz 60MHz [ON] [OFF] [ON] [ON] 66MHz [ON] [OFF] [ON] [ON] 60MHz ASUS C-P6ND User's Manual 3 III. INSTALLATION (Jumpers) J P1 5 JP14 J P1 6 JP2 JP3 JP2 JP3 III. INSTALLATION 3. Voltage Regulator Output Selection (JP2-5, 9-12) Pentium Pro Processors may require different voltages. Current processors (marked "Pentium Pro") support VID and will automatically adjust the voltage regulator so that no jumper settings are needed (leave these jumpers open in this case). Older processors without VID support require manual voltage ID setting. Use [S] for Short and [O] or Open. Selections JP5/9 (VID 0) JP4/10 (VID 1) JP3/11 (VID 2) JP2/12 (VID 3) 3.5 [S] [S] [S] [S] 3.4 [O] [S] [S] [S] 3.3 [S] [O] [S] [S] 3.2 [O] [O] [S] [S] 3.1 [S] [S] [O] [S] 3.0 [O] [S] [O] [S] 2.9 [S] [O] [O] [S] 2.8 [O] [O] [O] [S] 2.7 [S] [S] [S] [O] 2.6 [O] [S] [S] [O] 2.5 [S] [O] [S] [O] 2.4 [O] [O] [S] [O] 2.3 [S] [S] [O] [O] 2.2 [O] [S] [O] [O] 2.1 [S] [O] [O] [O] III. INSTALLATION (Jumpers) 4 VID Support (CPU 1) VID Support (CPU 0) Voltage ID 0, 1, 2, 3 (VID Support or Manual) 4. CPU cooling fan connector (JP1, JP8) This connector supports a CPU cooling fan of 500mAMP (6WATT) or less. Depending on the fan manufacturer, the wiring may be different. The red wire should be positive, while the black should be ground. Connect the fan to the board taking into consideration the polarity of the connector. WARNING: Damage may occur to the motherboard and/or the CPU fan if these pins are incorrectly used. These are not jumpers, do not place jumper caps over these pins. CPU Fan Power ASUS C-P6ND User's Manual III. INSTALLATION Software BIOS The BIOS on the two CPU cards are different. When adding a CPU card, find the BIOS chip that came with the CPU card and replace it with the one on the baseboard if one is present. Use the Flash Memory Writer utility to upgrade the BIOS version from the support diskette provided if necessary. You can find instruction on using the Flash memory Write utility at the end of the BIOS Software section IV. Power Connection Procedures 1. After all jumpers and connections are made, close the system case cover. 2. Make sure that all switches are in the off position as marked by . 3. Connect the power supply cord into the power supply located on the back of your system case as instructed by your system user's manual. III. INSTALLATION (Power Connections) 5 4. Connect all power cords into a power strip that is equipped by a surge protector. 5. You may then turn on your devices in the following order: a. Your monitor b. External SCSI devices (starting with the last device on the chain) c. Your system power 6. The power LED on the front panel of the system case will light and the monitor LED as well. The system will then run power-on tests. While the tests are running, additional messages will appear on the screen. If you do not see anything within 30 seconds from the time you turn on the power, the system may have failed a power-on test. Recheck your jumper settings and connections or call your authorized dealer for assistance. 7. During power-on, hold down the key to enter BIOS setup. Follow the next section "BIOS SOFTWARE" for instructions. ASUS C-P6ND User's Manual IV. BIOS SOFTWARE Support Software FILELIST.TXT - View this file to see the files included in the support software. PFLASH.EXE - This is the Flash Memory Writer utility that updates the BIOS by uploading a new BIOS file to the programmable flash ROM chip on the motherboard. To determine the BIOS version, check the last four numbers of the code displayed on the upper left-hand corner of your screen during bootup. Larger numbers represent a newer BIOS file. NOTE: A binary BIOS file is no longer included with the support software. Save the motherboard's BIOS file to a floppy diskette as soon as your system is operational. See "Flash Memory Writer Utility" in this section to "Save Current BIOS to File." Flash Memory Writer Utility ASUSTeK PNP BIOS FLASH MEMORY WRITER V1.5 Copyright (C) 1995, ASUSTeK COMPUTER Inc. Flash Type -- SST 29EE010 Current BIOS Revision: #401A0-xxxx Choose one of the following: 1. Save Current BIOS To File 2. Update BIOS Main Block From File 3. Advanced Features Enter Choice: [1] Press ESC To Exit IV. BIOS (Flash Memory Writer) 6 xxxx denotes the current BIOS version stored in the Flash EPROM IMPORTANT: Flash Type may also be "INTEL 28F001BXT." If "unknown" is shown after "Flash type --," then this ROM chip is not programmable or not supported with the PnP BIOS and therefore cannot be programmed by the Flash Memory Writer. Main Menu 1. Save Current BIOS to File (Perform as soon as system is operational) This option allows you to copy the contents of the Flash memory chip onto a diskette. This gives you a backup copy of the original motherboard BIOS in case you need to re-install it. Create a bootable system floppy diskette by typing [FORMAT A:/S] from the DOS environment without creating "AUTOEXEC.BAT" and "CONFIG.SYS" files, then save the PFLASH.EXE and the BIOS to the floppy diskette. ASUS C-P6ND User's Manual IV. BIOS SOFTWARE 2. Update BIOS Main Block from File This option updates the BIOS from a file on the disk. This can either be a new file or a backup file created by the "Save Current BIOS to File" option. This will not update the Boot Block if the Boot Block is different. You will be prompted with the following if advanced features if necessary. Boot Block of New BIOS is different from old one !!! Please Use 'Advanced Feature' to flash whole bios !!! 3. Advanced Features Selecting this option brings up the Advanced Features screen for clearing the PnP configuration record and updating the motherboard BIOS. Advanced Features Menu Advanced Features Flash Type -- SST 29EE010 Current BIOS Revision: #401A0-xxxx Choose one of the following: 1. Clear PNP ESCD Parameter Block 2. Update BIOS Including Boot Block and ESCD Enter Choice: [2] Press ESC To Exit xxxx denotes the current BIOS version stored in the Flash EPROM 1. Clear PNP ESCD Parameter Block This option erases the Plug-and-Play (PnP) configuration record. 2. Update BIOS Including Boot Block and ESCD This option updates the Boot Block, the motherboard BIOS and the PnP ESCD Parameter Block from a new BIOS file. NOTE: "Update BIOS Main Block from File" and "Update BIOS Including Boot Block and ESCD" requires that the system is running in real mode. This utility will not operate if the system is under protected mode or virtual mode. You should boot from a system floppy diskette without "AUTOEXEC.BAT" and "CONFIG.SYS" files. ASUS C-P6ND User's Manual 7 IV. BIOS (Flash Memory Writer) IV. BIOS SOFTWARE Updating your Motherboard's BIOS 1. Download an updated BIOS file from Bulletin Board Services (BBS) or the internet (WWW) and save to the diskette you created in step 1 of the Main Menu. See ASUS CONTACT INFORMATION on page II. 2. Turn off your computer and open the system cabinet to Enable "Boot Block Programming" jumper as shown in section III. 2. Boot from the floppy diskette you created in step 1 of the main menu. 3. At the "A:\" prompt, type: PFLASH 4. Enter "2" from the Main Menu or "2" from the Advanced Features Menu. 5. The program displays a second screen prompting you for the name of the BIOS file. Type in the complete name of the file, including the file name extension, and then press the key. The utility then uploads the BIOS file from disk. The following message will appear: DO NOT TURN OFF THE SYSTEM IF THERE IS A PROBLEM! If you encounter problems while downloading the new BIOS, DO NOT turn off your system since this might prevent your system from booting up. Just repeat the process, and if the problem still persists, upload the original BIOS file you saved to disk in step 1 of the Main Menu. WARNING: If the Flash Memory Writer utility was not able to successfully download a complete BIOS file, your system may not be able to boot up. If this happens, your system will require service from your vendor. 6. After successfully downloading the new BIOS file, exit the Flash Memory Writer utility and then turn off your system. Set the jumper back to its default setting of Programming "Disabled." 7. Turn on your computer and hold down to enter BIOS setup. You must select "Setup Default" to affect the new BIOS, then you may set other items from the Main Menu. IV. BIOS (Flash Memory Writer) 8 ASUS C-P6ND User's Manual IV. BIOS SOFTWARE BIOS Setup The motherboard supports two programmable Flash ROM chips: 5 Volt and 12 Volt. Either of these memory chips can be updated when BIOS upgrades are released. Use the Flash Memory Writer utility to download the new BIOS file into the ROM chip as described in detail in this section. All computer motherboards provide a Setup utility program for specifying the system configuration and settings. If your motherboard came in a computer system, the proper configuration entries may have already been made. If so, invoke the Setup utility, as described later, and take note of the configuration settings for future reference; in particular, the hard disk specifications. If you are installing the motherboard, reconfiguring your system or you receive a Run Setup message, you will need to enter new setup information. This section describes how to configure your system using this utility. The BIOS ROM of the system stores the Setup utility. When you turn on the computer, the system provides you with the opportunity to run this program. This appears during the Power-On Self Test (POST). Press the key to call up the Setup utility. If you are a little bit late pressing the mentioned key(s), POST will continue with its test routines, thus preventing you from calling up Setup. If you still need to call Setup, reset the system by simultaneously pressing the , and keys, or by pushing the Reset button on the system case. You can also restart by turning the system off and then back on again. But do so only if the first two methods fail. When you invoke Setup, the CMOS SETUP UTILITY main program screen will appear with the following options: ASUS C-P6ND User's Manual 9 IV. BIOS (BIOS Setup) IV. BIOS SOFTWARE Load Defaults The "Load BIOS Defaults" option loads the minimized settings for troubleshooting. "Load Setup Defaults", on the other hand, is for loading optimized defaults for regular use. Choosing defaults at this level, will modify all applicable settings. A section at the bottom of the above screen displays the control keys for this screen. Take note of these keys and their respective uses. Another section just below the control keys section displays information on the currently highlighted item in the list. Standard CMOS Setup This "Standard CMOS Setup" option allows you to record some basic system hardware configuration and set the system clock and error handling. If the motherboard is already installed in a working system, you will not need to select this option anymore. However, if the configuration stored in the CMOS memory on the board gets lost or damaged, or if you change your system hardware configuration, you will need to respecify the configuration values. The configuration values usually get lost or corrupted when the power of the onboard CMOS battery weakens. IV. BIOS (Standard CMOS) The above screen provides you with a list of options. At the bottom of this screen are the control keys for use on this screen. Take note of these keys and their respective uses. User-configurable fields appear in a different color. If you need information on the selected field, press the key. The help menu will then appear to provide you with the information you need. The memory display at the lower right-hand side of the screen is read-only and automatically adjusts accordingly. 10 ASUS C-P6ND User's Manual IV. BIOS SOFTWARE Details of Standard CMOS Setup: Date To set the date, highlight the "Date" field and then press the page up/page down or +/- keys to set the current date. Follow the month, day and year format. Valid values for month, day and year are: Month: Day: Year: 1 to 12 1 to 31 up to 2099 Time To set the time, highlight the "Time" field and then press the page up/page down or +/- keys to set the current time. Follow the hour, minute and second format. Valid values for hour, minute and second are: Hour: Minute: Second: 00 to 23 00 to 59 00 to 59 time, just press the key twice if you do not want to modify the current You can bypass the date and time prompts by creating an AUTOEXEC.BAT file. For information on how to create this file, please refer to the MS-DOS manual. Hard Disk Drives This field records the specifications for all non-SCSI hard disk drives installed in your system. The onboard PCI IDE connectors provide Primary and Secondary channels for connecting up to four IDE hard disks or other IDE devices. Each channel can support up to two hard disks; the first of which is the "master" and the second is the "slave". Specifications for SCSI hard disks need not to be entered here since they operate using device drivers and are not supported by any the BIOS. If you install the optional PCI-SC200 SCSI controller card into the motherboard (see section VI for instructions). If you install other vendor's SCSI controller card, please refer to their respective documentations on how to install the required SCSI drivers. ASUS C-P6ND User's Manual 11 IV. BIOS (Standard CMOS) IV. BIOS SOFTWARE For IDE hard disk drive setup, you can: · Use the Auto setting for detection during bootup. · Use the IDE HDD AUTO DETECTION in the main menu to automatically enter the drive specifications. · Enter the specifications yourself manually by using the "User" option. The entries for specifying the hard disk type include CYLS (number of cylinders), HEAD (number of read/write heads), PRECOMP (write precompensation), LANDZ (landing zone), SECTOR (number of sectors) and MODE. The SIZE field automatically adjusts according to the configuration you specify. The documentation that comes with your hard disk should provide you with the information regarding the drive specifications. The MODE entry is for IDE hard disks only, and can be ignored for MFM and ESDI drives. This entry provides three options: Normal, Large, LBA, or Auto (see below). Set MODE to the Normal for IDE hard disk drives smaller than 528MB; set it to LBA for drives over 528MB that support Logical Block Addressing (LBA) to allow larger IDE hard disks; set it to Large for drives over 528MB that do not support LBA. Large type of drive can only be used with MS-DOS and is very uncommon. Most IDE drives over 528MB support the LBA mode. Auto detection of hard disks on bootup For each field: Primary Master, Primary Slave, Secondary Master, and Secondary Slave, you can select Auto under the TYPE and MODE fields. This will enable auto detection of your IDE drives during bootup. This will allow you to change your hard drives (with the power off) and then power on without having to reconfigure your hard drive type. If you use older hard drives which do not support this feature, then you must configure the hard drive in the standard method as described above by the "User" option. IV. BIOS (Standard CMOS) 12 NOTE: After the IDE hard disk drive information has been entered into BIOS, new IDE hard disk drives must be partitioned (such as with FDISK) and then formatted before data can be read from and write on. Primary IDE hard disk drives must have its partition set to active (also possible with FDISK). ASUS C-P6ND User's Manual IV. BIOS SOFTWARE Drive A, Drive B These fields record the types of floppy disk drives installed in your system. The available options for drives A and B are: 360KB, 5.25 in. 1.2MB, 5.25 in. 720KB, 3.5 in. 1.44MB, 3.5 in. 2.88MB, 3.5 in. None To enter the configuration value for a particular drive, highlight its corresponding field and then select the drive type using the left- or right-arrow key. Floppy 3 Mode Support This is the Japanese standard floppy drive. The standard stores 1.2MB in a 3.5" diskette. This is normally disabled but you may choose from either: Drive A Drive B Both Disabled (Default) EGA/VGA (Default) Mono (for Hercules or MDA) CGA 40 CGA 80 If you are using a VGA or any higher resolution card, choose the "EGA/VGA" option. Halt On This field determines which types of errors will cause the system to halt. All Errors (Default) No Errors All, But Keyboard All, But Diskette All, But Disk/Key ASUS C-P6ND User's Manual 13 IV. BIOS (Standard CMOS) Video Set this field to the type of video display card installed in your system. The options are: IV. BIOS SOFTWARE BIOS Features Setup This "BIOS Features Setup" option consists of configuration entries that allow you to improve your system performance, or let you set up some system features according to your preference. Some entries here are required by the motherboard's design to remain in their default settings. A section at the lower right of the screen displays the control keys you can use. Take note of these keys and their respective uses. If you need information on a particular entry, highlight it and then press the key. A pop-up help menu will appear to provide you with the information you need. To load the last set values, press the key. and load the BIOS default values and Setup default values, respectively. IV. BIOS (BIOS Features) 14 Details of BIOS Features Setup: Virus Warning This field protects the boot sector and partition table of your hard disk against accidental modifications. Any attempt to write to them will cause the system to halt and display a warning message. If this occurs, you can either allow the operation to continue or use a bootable virus-free floppy disk to reboot and investigate your system. The default setting is Disabled. This setting is recommended because conflicts with new operating systems. Installation of new operating systems require that you disable this to prevent write errors. CPU Level 1 Cache / CPU Level 2 Cache These fields allow you to choose from the default of Enable or choose Disable to turn on or off the CPU's Level 1 and Level 2 built-in cache. BIOS Update This functions as an update loader integrated into the BIOS to correct specific versions of the Pentium Pro processor. The BIOS will load the update on all processors during system bootup in the default position of Enabled. ASUS C-P6ND User's Manual