Upgrading the System BIOS

When you upgrade an existing system without replacing the motherboard, the BIOS version it uses can be a critical issue. Some system features—notably support for large hard disks, high-speed transfer modes, and AGP—are BIOS-dependent, so an in-place upgrade often requires a BIOS upgrade as well. Fortunately, recent systems use a flash BIOS, which can be upgraded simply by downloading a later version of the BIOS to replace the existing BIOS.


Be extraordinarily careful when upgrading a flash BIOS. Before you proceed, make absolutely sure that the BIOS upgrade patch you are about to apply is the exact one required for the current BIOS. If you apply the wrong patch, you may render your system unbootable from the floppy drive, which makes it difficult or impossible to recover by reapplying the proper patch.

Upgrading a flash BIOS requires two files. The first is the upgraded BIOS itself in binary form. The second is the “flasher” program provided by the BIOS manufacturer, e.g., awdflash.exe. The exact steps you follow to upgrade a flash BIOS vary slightly according to the BIOS manufacturer and the version of the flasher program you are using, but the following steps are typical:

  1. Before proceeding, record all current BIOS settings, either using pencil and paper or a utility program that writes BIOS settings to a disk file. If you have a UPS, connect the system to it for the duration of the BIOS update. Losing power during a BIOS update can result in ...

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