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PC Hacks
By Jim Aspinwall
October 2004
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Upgrade Your Flash BIOS

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Sometimes only after a product gets to market and is used in a lot of different situations can a vendor learn of problems or limitations. Nearly every system board and PC system on the market undergoes at least one significant revision of the BIOS after the product has been released for sale.

Most of us think nothing of seeking out the latest patches and updates for our application software and hardware drivers in hopes of solving a problem, gaining a feature, or boosting performance, but rarely do we think of updating the software and internal drivers that make our system board tick—the system BIOS.

I highly recommend visiting the web site of the manufacturer of your PC system or system board, or even Unicore's web site, to learn what the latest revision of BIOS is for your PC and the issues the revision addresses. You may find one or more clues that can help you solve problems or gain new or proper functionality of your system for a few minutes of browsing and downloading time.


Do not bother visiting the BIOS makers' web sites looking for BIOS updates. AMI and Award/Phoenix supply only the tools and services for system-board and PC-system makers to create their own BIOS code specific to each individual system board.

You wouldn't think of calling Microsoft, makers of the Visual Studio program development tools, about support or upgrades for software made by Adobe, Intuit, Symantec, or other software makers who use the Visual Studio tools. Nor would you call Sears about problems with your house built with a Craftsman hammer. And so it is with the BIOS companies.

A good resource for identifying your system board is the http://www.motherboards.org web site.

In most cases, except getting a BIOS upgrade from Unicore, getting a BIOS update and the software program to load the update into your PC are free from every system board and PC maker's web site. Since many of the devices you add to a system after the initial purchase are too new to be known to or supported by system board vendors, BIOS upgrades are issued to fix anything from an all-out serious bug that prevents some aspect of the system board from working, to enhancing the detection or size of certain types of disk drives, to adding extra support for Plug and Play or power management functions. These items should be spelled out in a readme or BIOS revision description file associated with the particular BIOS version you download.


Updating the system BIOS involves overwriting the BIOS code currently stored on the system board and replacing it with new code. This process has the potential to render your system board useless if there is an error or interruption while the update is occurring. If the BIOS file you download is incomplete or corrupt in any way, you will not be able to properly load the BIOS into the system board.

Part of the overall BIOS upgrade process should include backing up the current BIOS onto disk. If your system does not behave correctly after the upgrade, you can flash it with a new good BIOS file or use the original backed-up BIOS file to go back to a known good state.

Depending on your motherboard's capabilities, you may or may not be able to recover from a flashing accident. Intel provides a downloadable recovery BIOS, which can recover certain Intel motherboards after a failed BIOS upgrade. You can locate your recovery BIOS by visiting http://downloadfinder.intel.com, navigating to your motherboard, and selecting the recovery BIOS, if one is available.

A typical BIOS file is either 128 or 256 KB in size, though some may be as large as 2 MB, depending on features. The typical BIOS file, along with the program for updating your system board, both fit on a single 1.44 MB DOS-bootable formatted diskette. If you lack a diskette drive for your system, as may be the case for a laptop PC, you can also use a bootable CD containing the BIOS file and update program.


Some BIOS upgrade programs are available for use under Windows, which, although convenient and more user-friendly, has the risk of failing due to a crash, conflict, or other instability within Windows. I recommend using a DOS-based BIOS upgrade program if it is available.

Some BIOS update programs create their own bootable diskettes and execute the upgrade process automatically so you need only supply the diskette. Once you have downloaded the BIOS file (usually a .BIN file extension type) and BIOS update program to your hard drive, follow the instructions provided with the upgrade (likely proceeding from Step 8 below) or all of the following steps to update your system's BIOS.


Be sure your computer is plugged into a UPS (Uninterruptible Power Supply). All it takes is a power outage during a BIOS upgrade to render your motherboard useless.

  1. Prepare a formatted DOS boot diskette. Any version of DOS should do, but making a DOS 6.22, Windows 95, 98, or Me startup diskette would be most common. You can also make an MS-DOS startup disk using the format program in Windows XP, downloading boot diskette images from http://www.bootdisk.com.

  2. If in Windows, double-click My Computer, then double-click the A: drive.

  3. In DOS or Windows, delete the following files from the diskette to make room for the BIOS files:

    • All ASPIxxxx.SYS files

    • All BTxxxxxx.SYS files



    • EBD.CAB




  4. Copy the specific BIOS (.BIN) file to the diskette.

  5. Copy the BIOS upgrade program to the diskette.

  6. Restart the PC with the diskette in the drive so the system boots from the floppy. You may need to change the boot device order [Hack#6] first.

  7. At the DOS prompt type in the name of the BIOS upgrade program and press the Enter key to run it. You should be presented with a text menu of options.

  8. One of the options should be to copy the existing FLASH ROM BIOS to disk as a backup—do this. (Often the upgrade process will automatically prompt to copy a backup of the BIOS to disk.)

  9. Select the option to program the new BIOS file into the FLASH ROM. If you are presented with the option, and you did not already make a backup of the existing BIOS, do so now.

  10. Follow the prompts to upgrade your BIOS. In some cases, you will need to provide the name of the new BIOS file and let the program copy the file into the FLASH ROM.

  11. When the programming process completes, remove the diskette from the drive and then restart the PC. If your computer displays the BIOS version at boot time, you should notice the new BIOS version appear on screen.

  12. Go into the BIOS setup program. Verify or set the date, time, and other parameters you're familiar with and then restart the PC. You're done with the BIOS upgrade.


Do not forget to check the web site of your video card, disk drive, printer, and USB-connected product vendors for any BIOS or firmware updates for these devices.

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