Asus A7N8X: Chapter 4

Chapter 4

BIOS setup

ASUS A7N266-VM motherboard

4.1 Managing and updating your BIOS

4.1.1 Using the computer system for the first time

It is recommended that you save a copy of the original motherboard BIOS

along with a Flash Memory Writer utility (AFLASH.EXE) to a bootable floppy

disk in case you need to reinstall the BIOS later. AFLASH.EXE is a Flash

Memory Writer utility that updates the BIOS by uploading a new BIOS file to

the programmable flash ROM on the motherboard. This file works only in

DOS mode. To determine the BIOS version of your motherboard, 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.

1. Type FORMAT A:/S at the DOS prompt to create a bootable system disk.

DO NOT copy AUTOEXEC.BAT and CONFIG.SYS to the disk.

2. Type COPY D:\AFLASH\AFLASH.EXE A:\ (assuming D is your CD-ROM

drive) to copy AFLASH.EXE to the boot disk you created.

NOTE! AFLASH works only in DOS mode. It does not work in the DOS

prompt within Windows, and does not work with certain memory drivers

that may be loaded when you boot from the hard drive. It is recommended

that you reboot using a floppy disk.

3. Reboot the computer from the floppy disk.

NOTE! BIOS setup must specify “Floppy” as the first item in the boot

sequence.

4. In DOS mode, type A:\AFLASH <Enter> to run AFLASH.

IMPORTANT! If the word “unknown” appears after Flash Memory:, the

memory chip is either not programmable or is not supported by the ACPI

BIOS and therefore, cannot be programmed by the Flash Memory Writer

utility.

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5. Select 1. Save Current BIOS to File from the Main menu and press

<Enter>. The Save Current BIOS To File screen appears.

6. Type a filename and the path, for example, A:\XXX-XX.XXX, then

press <Enter>.

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Chapter 4: BIOS Setup

4.1.2 Updating BIOS procedures

CAUTION! Update the BIOS only if you have problems with the

motherboard and you are sure that the new BIOS revision will solve your

problems. Careless updating may result to more problems with the

motherboard!

1. FTP) (see ASUS CONTACT INFORMATION on page x for details) and

save to the boot floppy disk you created earlier.

2. Boot from the floppy disk.

3. At the “A:\” prompt, type AFLASH and then press <Enter>.

4. At the Main Menu, type 2 then press <Enter>. The Update BIOS Including

Boot Block and ESCD screen appears.

5. Type the filename of your new BIOS and the path, for example, A:\XXX-

XX.XXX, then press <Enter>.

To cancel this operation, press <Enter>.

6. When prompted to confirm the BIOS update, press Y to start the

update.

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7. The utility starts to program the new BIOS information into the Flash

ROM. The boot block is updated automatically only when necessary.

This minimizes the possibility of boot problems in case of update failures.

When the programming is done, the message “Flashed Successfully”

appears.

8. Follow the onscreen instructions to continue.

WARNING! If you encounter problems while updating the new BIOS,

DO NOT turn off the system because this may cause boot problems.

Just repeat the process, and if the problem persists, load the original

BIOS file you saved to the boot disk. If the Flash Memory Writer utility is

not able to successfully update a complete BIOS file, the system may not

boot. If this happens, call the ASUS service center for support.

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Chapter 4: BIOS Setup

4.2 BIOS Setup program

This motherboard supports a programmable EEPROM that you can update

using the provided utility described in section “4.1 Managing and updating

your BIOS.”

Use the BIOS Setup program when you are installing a motherboard,

reconfiguring your system, or prompted to “Run Setup”. This section explains

how to configure your system using this utility.

Even if you are not prompted to use the Setup program, you may want to

change the configuration of your computer in the future. For example, you

may want to enable the security password feature or make changes to the

power management settings. This requires you to reconfigure your system

using the BIOS Setup program so that the computer can recognize these

changes and record them in the CMOS RAM of the EEPROM.

The EEPROM on the motherboard stores the Setup utility. When you start

up the computer, the system provides you with the opportunity to run this

program. Press <Delete> during the Power-On Self Test (POST) to enter the

Setup utility, otherwise, POST continues with its test routines.

If you wish to enter Setup after POST, restart the system by pressing <Ctrl>

+ <Alt> + <Delete>, or by pressing the reset button on the system chassis.

You can also restart by turning the system off and then back on. Do this last

option only if the first two failed.

The Setup program is designed to make it as easy to use as possible. It is a

menu-driven program, which means you can scroll through the various sub-

menus and make your selections among the predetermined choices.

NOTE! Because the BIOS software is constantly being updated, the

following BIOS setup screens and descriptions are for reference purposes

only, and may not exactly match what you see on your screen.

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4.2.1 BIOS menu bar

The top of the screen has a menu bar with the following selections:

MAIN Use this menu to make changes to the basic system

configuration.

ADVANCED Use this menu to enable and make changes to the

advanced features.

POWER Use this menu to configure and enable Power Management

features.

BOOT Use this menu to configure the default system device used

to locate and load the Operating System.

EXIT Use this menu to exit the current menu or to exit the Setup

program.

To access the menu bar items, press the right or left arrow key on the keyboard

until the desired item is highlighted.

4.2.2 Legend bar

At the bottom of the Setup screen is a legend bar. The keys in the legend bar

allow you to navigate through the various setup menus. The following table

lists the keys found in the legend bar with their corresponding functions.

Navigation Key(s) Function Description

<F1> or <Alt + H> Displays the General Help screen from any-

where in the BIOS Setup

<Esc> Jumps to the Exit menu or returns to the main

menu from a sub-menu

Left or Right arrow Selects the menu item to the left or right

Up or Down arrow Moves the highlight up or down between fields

- (minus key) Scrolls backward through the values for the

highlighted field

+ (plus key) or spacebar Scrolls forward through the values for the high-

lighted field

<Enter> Brings up a selection menu for the highlighted

field

<Home> or <PgUp> Moves the cursor to the first field

<End> or <PgDn> Moves the cursor to the last field

<F5> Resets the current screen to its Setup Defaults

<F10> Saves changes and exits Setup

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Chapter 4: BIOS Setup

General help

In addition to the Item Specific Help window, the BIOS setup program also

provides a General Help screen. You may launch this screen from any menu

by simply pressing <F1> or the <Alt> + <H> combination. The General Help

screen lists the legend keys and their corresponding functions.

Saving changes and exiting the Setup program

See “4.7 Exit Menu” for detailed information on saving changes and exiting

the setup program.

Scroll bar

When a scroll bar appears to the right of a help window, it indicates that

there is more information to be displayed that will not fit in the window. Use

<PgUp> and <PgDn> or the up and down arrow keys to scroll through the

entire help document. Press <Home> to display the first page, press <End>

to go to the last page. To exit the help window, press <Enter> or <Esc>.

Sub-menu

Note that a right pointer symbol (as shown on

the left) appears to the left of certain fields. This

pointer indicates that you can display a sub-

menu from this field. A sub-menu contains

additional options for a field parameter. To

display a sub-menu, move the highlight to the

field and press <Enter>. The sub-menu appears.

Use the legend keys to enter values and move

from field to field within a sub-menu as you would

within a menu. Use the <Esc> key to return to

the main menu. Take some time to familiarize

yourself with the legend keys and their

corresponding functions. Practice navigating through the various menus and

sub-menus. If you accidentally make unwanted changes to any of the fields,

use the set default hot key <F5> to load the Setup default values. While

moving around through the Setup program, note that explanations appear in

the Item Specific Help window located to the right of each menu. This window

displays the help text for the currently highlighted field.

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Language [English]

This field displays the BIOS language version.

Supervisor Password [Disabled] / User Password [Disabled]

These fields allow you to set passwords. To set a password, highlight the

appropriate field and press <Enter>. Type in a password then press <Enter>.

You can type up to eight alphanumeric characters. Symbols and other

characters are ignored. To confirm the password, type the password again

and press <Enter>. The password is now set to [Enabled]. This password

allows full access to the BIOS Setup menus. To clear the password, highlight

this field and press <Enter>. The same dialog box as above appears. Press

<Enter>. The password is set to [Disabled].

A note about passwords

The BIOS Setup program allows you to specify passwords in the Main

menu. The passwords control access to the BIOS during system startup.

Passwords are not case sensitive, meaning, passwords typed in either

uppercase or lowercase letters are accepted. The BIOS Setup program

allows you to specify two different passwords: a Supervisor password

and a User password. If you did not set a Supervisor password, anyone

can access the BIOS Setup program. If you did, the Supervisor password

is required to enter the BIOS Setup program and to gain full access to

the configuration fields.

Forgot the password?

If you forget your password, you can clear it by erasing the CMOS Real

Time Clock (RTC) RAM. The RAM data containing the password

information is powered by the onboard button cell battery. See section

“2.7Switches and jumpers” for information on how to erase the R TC

RAM.

Halt On [All Errors]

This field specifies the types of errors that will cause the system to halt.

Configuration options: [All Errors] [No Error] [All but Keyboard] [All but Disk]

[All but Disk/Keyboard]

Installed Memory [XXX MB]

This field automatically displays the amount of conventional memory detected

by the system during the boot process.

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Chapter 4: BIOS Setup

4.4 Advanced Menu

CPU Speed

This field displays the internal frequency of your CPU.

CPU/PCI Frequency (MHz) [100/33]

This feature tells the clock generator which frequency to send to the system

bus and PCI bus. The bus frequency (external frequency) multiplied by the

bus multiple equals the CPU speed. Increasing the ratio will increase the

CPU Speed. The range may not be modified in BIOS, but only changes

according to BSEL jumper settings.

CPU/Memory Frequency Ratio [Auto]

This field determines whether the memory clock frequency is set to be in

synchronous or asynchronous mode with respect to the memory frequency.

The options that appear in the popup menu vary according to the status of

the CPU/PCI Frequency (MHz) field. The range may not be modified in

BIOS, but only changes according to BSEL jumper settings.

CPU Level 1 Cache, CPU Level 2 Cache [Enabled]

These fields allow you to choose from the default of [Enabled] or choose

[Disabled] to turn on or off the CPU Level 1 and Level 2 built-in cache.

Configuration options: [Disabled] [Enabled]

CPU Level 2 Cache ECC Check [Enabled]

This function controls the ECC capability in the CPU level 2 cache.

Configuration options: [Disabled] [Enabled]

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CPU Fast Decode [Disabled]

This field functions as a supplemntary speed enhancement device for

streamlining CPU calculations. Configuration options: [Enabled] [Disabled]

BIOS Update [Enabled]

This field functions as an update loader integrated into the BIOS to supply

the processor with the required data. When set to [Enabled], the BIOS loads

the update on all processors during system bootup. Configuration options:

[Disabled] [Enabled]

PS/2 Mouse Function Control [Auto]

The default setting [Auto] allows the system to detect a PS/2 mouse at

startup. If a mouse is detected, the BIOS assigns IRQ12 to the PS/2

mouse. Otherwise, IRQ12 can be used for expansion cards. When you set

this field to [Enabled], BIOS always reserves IRQ12, whether or not a PS/2

mouse is detected at startup. Configuration options: [Enabled] [Auto]

USB Legacy Devices Support [Disabled]

This motherboard supports Universal Serial Bus (USB) devices. The default

of [Disabled] allows the system to detect a USB device at startup. The other

two fields [Primary] and [Secondary] are used to activate which ports are

activated: USB01 and USB23 or USB45. Users should select [Disabled] or

[Primary] to activate a USB-type keyboard connection to a new system.

Configuration options: [Disabled] [Primary] [Secondary] [USB Floppy Zip]

OS/2 Onboard Memory > 64M [Disabled]

When using OS/2 operating systems with installed DRAM of greater than

64MB, you need to set this option to [Enabled]. Otherwise, leave to the default

setting [Disabled]. Configuration options: [Disabled] [Enabled]

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Chapter 4: BIOS Setup

4.4.1 Summary of Warning Messages

(Jumperless Operation only)

The system may crash or hang up due to conflicts between settings and

CPU compatibility: checksum errors, improper frequency settings, change

of CPU and improper CPU speed settings. The system starts up in safe

mode running at a bus speed of 100MHz and enters the BIOS Setup. Each

time a system hangup occurs, BIOS interrupts the bootup process with a

specific warning message. These messages always appear on the right

side of the BIOS screen in red print:

1. Cause for Hangup: Checksum Error Warning

“The CMOS checksum is incorrect. Please reload the cmos default

value.” To solve this problem, clear the CMOS RTC memory (see pages

22 and 59) and then reenter the default values in the BIOS Exit menu

and restart the system.

2. Cause for Hangup: Improper System Frequency

“Last time you failed to change the frequency of the system. It may place

the system into an unstable state. Now the system is in safe mode at the

slowest CPU speed. Please set the system frequency again.” To solve

this problem, a slower frequency is more likely to obtain stable start-ups.

CPU Upgrade/Reinstallation

To ensure that the system can enter BIOS Setup after replacing the processor,

the system starts up running at a bus speed of 100MHz and a fail-safe CPU

internal frequency. Then it automatically enters the Advanced menu with a

popup display of all the possible CPU internal frequencies for the particular

CPU presently installed:

3. Cause for Hangup: Improper CPU Speed 1

“During the last bootup, your system hung for an improper CPU Speed

setting. Your system is now working in safe mode. To optimize the system

performance and stability, make sure the CPU speed conforms to the

specifications of your CPU.”

4. Cause for Hangup: Improper CPU Speed 2

“Since you are using a new CPU or have reinstalled your CPU, the system

boots up at the slowest CPU bus frequency to make sure the system can

enter setup menu. Now, you can adjust the CPU speed as you wish. If

the speed is adjusted too high, the system may hang. Please turn off the

system and then restart to set the CPU speed.”

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4.4.2 Chip Configuration

(Scroll down to view all items on the menu.)

SDRAM Configuration [By SPD]

This sets the optimal timing. The default setting is [By SPD], which

automatically configures the timing by reading the contents in the SPD (Serial

Presence Detect) device. The EEPROM on the memory module stores critical

parameter information about the module, such as memory type, size, speed,

voltage interface, and module banks. Configuration options: [User Defined]

[By SPD]

NOTE: The subfield below only be used if the SDRAM Configuration can

be changed to [User Defined].

SDRAM CAS Delay [Auto (Normal)]

Sets the latency between the SDRAM active command and the read/

write command. Configuration options: [Auto (Normal)] [2.0T (Normal)]

[2.5T (Normal)] [Auto (TURBO)] [2.0T (TURBO)] [2.5T (TURBO)]

Clock Spread Spectrum Mode [Center Spread]

Not available in this model. Configuration options: [Center Spread] [Spread

Down] [Disabled]

VGA Shared Memory Size [32MB]

This feature sets the size of mapped memory for VGA monitor data.

Configuration options: [8MB] [16MB] [32MB]

Graphics Aperture Size [64MB]

This feature sets the size of mapped memory for AGP graphic data.

Configuration options: [32MB] [64MB] [128MB] [256MB] [512MB]

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Chapter 4: BIOS Setup

Internal Graphic Over-clocking [Disable]

This feature permits the grapical processor to participate in over-clocking.

Configuration options: [Disable] [Enable]

Internal VGA LCD TV Display Type [NTSC-M]

The system automatically detects and sets up screen-type compatibility.

Configuration options: [NTSC-M] [NTSC-J] [PAL-M] [PAL-BDGHI]

[PAL-N] [PAL-NC]

Video Memory Cache Mode [UC]

USWC (uncaheable, speculative write combining) is a new cach technology

for the processor’s video memory. It can greatly improve the display speed

by caching the display data. Set this to UC (uncacheable) if the display card

cannot support this feature; otherwise, the system may not boot up.

Configuration options: [UC] [USWC]

Onboard VGA BIOS Update [Enabled]

Configuration options: [Enabled] [Disabled]

MCP IDE Controller [Both]

Configuration options: [Both] [Primary] [Secondary] [Disabled]

MCP USB Controller [Enabled]

Both USB controllers are enabled by default. Refer to USB Legacy

Keyboard support for specifying which ports are used to enable USB keyboard

support. Configuration options: [Enabled] [Disabled]

MCP Audio Controller [Auto]

Configuration options: [Enabled] [Disabled]

MCP MAC Controller [Enabled]

Configuration options: [Disabled] [Auto]

MCP DOLBY DIGITAL Controller [Auto]

Only available on motherboards featuring the MCP-D chipset. Configuration

options: [Disabled] [Auto]

PCI 2.1 Support [Enabled]

Configuration options: [Disabled] [Enabled]

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4.4.3 I/O Device Configuration

Onboard FDC Swap A & B [No Swap]

This field allows you to reverse the hardware drive letter assignments of

your floppy disk drives. Configuration options: [No Swap] [Swap AB]

Floppy Disk Access Control [R/W]

Set this field to read and write the floppy disk (R/W). Change to [Read Only]

for reading disks.

Onboard Serial Port 1 [3F8H/IRQ4]

Onboard Serial Port 2 [2F8H/IRQ3]

These fields allow you to set the addresses for the onboard serial connectors.

Serial Port 1 and Serial Port 2 must have different addresses. Configuration

options: [3F8H/IRQ4] [2F8H/IRQ3] [3E8H/IRQ4] [2E8H/IRQ10] [Disabled]

UART2 Use Standard Infrared [Disabled]

This field can activate the onboard standard infrared feature and sets the

second serial UART to support the infrared module connector on the

motherboard. See IrDA-Compliant Infrared Module Connector in 3.8

Connectors. Configuration options: [Disabled] [Enabled]

Onboard Parallel Port [378H/IRQ7]

This field sets the address of the onboard parallel port connector. If you

disable this field, the Parallel Port Mode and ECP DMA Select configurations

are not available. Configuration options: [Disabled] [378H/IRQ7] [278H/IRQ5]

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Chapter 4: BIOS Setup

Parallel Port Mode [ECP+EPP]

This field allows you to set the operation mode of the parallel port. [Normal]

allows normal-speed operation but in one direction only; [EPP] allows

bidirectional parallel port operation; [ECP] allows the parallel port to operate

in bidirectional DMA mode; [ECP+EPP] allows normal speed operation in a

two-way mode. Configuration options: [Normal] [EPP] [ECP] [ECP+EPP]

ECP DMA Select [3]

This field allows you to configure the parallel port DMA channel for the selected

ECP mode. This selection is available only if you select [ECP] or [ECP+EPP]

in Parallel Port Mode above. Configuration options: [1] [3] [Disabled]

Onboard Game Port [200H-207H]

This field sets the I/O address to the game port. Configuration options: [200H-

207H] [208H-20FH] [Disabled]

Onboard MIDI [Disabled]

This field sets the I/O address for MIDI. Configuration options: [330H-331H]

[300H-301H] [Disabled]

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4.4.4 PCI Configuration

Slot 1, Slot 2, Slot 3 [Auto]

These fields automatically assign the IRQ for each PCI slot. The default

setting for each field is [Auto], which utilizes auto-routing to determine IRQ

assignments. Configuration options: [Auto] [NA] [3] [4] [5] [7] [9] [10] [11] [12]

[14] [15]

PCI/VGA Palette Snoop [Disabled]

Some non-standard VGA cards, such as graphics accelerators or MPEG

video cards, may not show colors properly. Setting this field to [Enabled]

corrects this problem. If you are using standard VGA cards, leave this field

to the default setting [Disabled]. Configuration options: [Disabled] [Enabled]

PCI Latency Timer [32]

Leave this field to the default setting [32] for best performance and stability.

Primary VGA BIOS [AGP VGA Card]

This field allows you to select the primary graphics card. Select the [Onboard

VGA Card] option for optimal graphical support. Configuration options: [AGP

VGA Card] [Onboard VGA]

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Chapter 4: BIOS Setup

PCI DMA Resource Exclusion

DMA x Reserved for Legacy Drive [No/ICU]

These fields indicate whether or not the DMA channel displayed for each

field is being used by a legacy (non-PnP) ISA card. The default setting

indicates either that the DMA channel displayed is not used or an ICU is

being used to determine if an ISA device is using the channel instead.

Configuration options: [No/ICU] [Yes]

PCI UMB Resource Exclusion

TSM MEM Block BASE [No/ICU]

This field allows yout to set the base address and block size of an onboard

legacy ISA device that uses any memory segment within the C800 and DFFF

address range. With such a device, select a base address from the options.

If an ICU is already in use, then leave the TSM MEM Block BASE to its

default setting of [No/ICU]. Configuration options: [No/ICU] [C800] [CC00]

[D000] [D400] [D800] [DC00]

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Boot Virus Detection [Enabled]

This field allows you to set boot virus detection, ensuring a virus-free boot

sector. The system halts and displays a warning message when it detects a

virus. If this occurs, you can either allow the operation to continue or use a

virus-free bootable floppy disk to restart and investigate your system.

Configuration options: [Disabled] [Enabled]

Quick Power On Self Test [Enabled]

This field speeds up the Power-On-Self Test (POST) routine by skipping

retesting a second, third, and fourth time. Configuration options: [Disabled]

[Enabled]

Boot Up Floppy Seek [Enabled]

When enabled, the BIOS will seek the floppy disk drive to determine whether

the drive has 40 or 80 tracks. Configuration options: [Disabled] [Enabled]

Interrupt Mode [APIC]

Configuration options: [APIC] [PIC]

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Chapter 4: BIOS Setup

4.7 Exit Menu

When you have made all of your selections from the various menus in the

Setup program, save your changes and exit Setup. Select Exit from the

menu bar to display the following menu.

NOTE! Pressing <Esc> does not immediately exit this menu. Select

one of the options from this menu or <F10> from the legend bar to exit.

Exit Saving Changes

Once you are finished making your selections, choose this option from the

Exit menu to ensure the values you selected are saved to the CMOS RAM.

The CMOS RAM is sustained by an onboard backup battery and stays on

even when the PC is turned off. When you select this option, a confirmation

window appears. Select [Yes] to save changes and exit.

NOTE! If you attempt to exit the Setup program without saving your

changes, the program prompts you with a message asking if you want to

save your changes before exiting. Pressing <Enter> saves the changes

while exiting.

Exit Discarding Changes

Select this option only if you do not want to save the changes that you made

to the Setup program. If you made changes to fields other than system date,

system time, and password, the BIOS asks for a confirmation before exiting.

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Load Setup Defaults

This option allows you to load the default values for each of the parameters

on the Setup menus. When you select this option or if you press <F5>, a

confirmation window appears. Select [Yes] to load default values. Select Exit

Saving Changes or make other changes before saving the values to the

non-volatile RAM.

Discard Changes

This option allows you to discard the selections you made and restore the

previously saved values. After selecting this option, a confirmation appears.

Select [Yes] to discard any changes and load the previously saved values.

Save Changes

This option saves your selections without exiting the Setup program. You

can then return to other menus and make further changes. After you select

this option, a confirmation window appears. Select [Yes] to save any changes

to the non-volatile RAM.

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Chapter 4: BIOS Setup