The oldest way of performing a BIOS upgrade is by using a DOS-based utility. Nowadays, this is very complicated, as you will need a bootable DOS floppy (or a bootable DOS CD-ROM) to use this kind of program. This floppy can only be created on Windows up to Millenium Edition (ME), as Windows NT, 2000, XP, Vista, and 7 do not provide an option to create a DOS bootable floppy.
Don’t try running the DOS programmer inside Windows. It won’t work.
If you have access to a computer with Windows up to ME installed, you can create a bootable floppy by inserting a floppy in the floppy disk drive, going to My Computer and right clicking on A:, selecting Format. On the screen that will show up, check the “System” checkbox and then click on Format. Format a: /s command will also do the trick.
If you don’t have access to a computer running an older operating system, you can download a pre-made boot disk at http://www.bootdisk.com/bootdisk.htm. Download the DOS 6.22 floppy and execute the .exe file to create the bootable floppy.
After creating this DOS boot disk, copy both the programmer (a .com or .exe file; in our case, it was called Awdflash.exe) and the BIOS file (usually a .com or .bin file; in our example we will be using a file called 485_v10c.bin).
Enter setup and change the boot order (in an option called Boot Sequence or similar) to allow booting from the floppy disk drive before the hard disk drive. Exit saving the changes. Insert your floppy disk into the floppy disk drive and load DOS from it.
After you see the DOS prompt (the famous A:\>), enter the BIOS programmer name followed by the BIOS file name. In our case, the command was:
Awdflash 485_v10c.bin
Then the screen shown in Figure 18 was presented.

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Figure 18: DOS programmer main screen
As you can see, the first thing the programmer asks us is if we want to backup the current BIOS used by our motherboard. Answer “Y” and save it to the floppy disk as “old_bios.bin” or something similar.

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Figure 19: Saving the current BIOS to a file

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Figure 20: Saving the current BIOS to a file
Next the program will confirm if we really want to upgrade the BIOS. Hit “Y” and wait while it upgrades the BIOS chip.

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Figure 21: Confirmation screen
After the BIOS was upgraded, simply reset your system and that’s it.

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Figure 22: BIOS successfully upgraded
Don’t forget to remove your floppy disk from the floppy disk drive and also to enter setup, and set back your hard disk drive as the first boot option.