Can My BIOS Be Fixed?
BackBy Avner Izhar —
Q: I need help to either recover or replace my AMIBIOS. I tried to update the BIOS inside of Windows using the AMIFlash. It said it failed, so I gathered the tools to do it in DOS. When I rebooted, I got nothing — no beeps, no lights, just the power supply, fan and heatsink. Any ideas?
A: This one is very hard, and the AMIBIOS might not be recoverable at all. One of my main recommendations is don’t update your BIOS unless you have a spare set available.
Before discussing some recovery techniques, let’s first outline what the BIOS is. BIOS stands for Basic Input/Output System, and it’s the first set of commands that a CPU will execute when the computer is powered on. It will set the initial ways your hardware components will communicate with you and each other.
The BIOS software is stored on a memory chip that’s not volatile (i.e., erased when turned off). The user settings part in it — which defines which device is your first boot device (CD/DVD, USB or hard drive) — is volatile, but is backed up using a battery when the computer is turned off.
Prior to the early 1990s, BIOS programs were stored in read-only memory (ROM) or programmable read-only memory (PROM) chips, which could not be altered by users.
As the complexity of BIOS and the need for updates increased and reprogrammable parts became available more easily, BIOS firmware was stored on memory chips that allowed updates.
The updatable memory chips are subject to the risk that an improperly executed or aborted BIOS update could render the computer or device unusable.
To avoid these situations, the more recent BIOS use a “boot block” — a portion of the BIOS that runs first and must be updated separately. This code verifies if the rest of the BIOS is in good shape and can do its part before transferring control to it. If the boot block detects any corruption in the main BIOS, it will usually warn the user that a recovery process must be initiated by booting from removable media — CD or USB memory — so the user can try flashing the BIOS again.
Some motherboards have a backup BIOS (Dual BIOS boards) to recover from BIOS corruptions. According to your description, your BIOS isn’t communicating at all since the beeps and the display output are coming from it.
This may still be recoverable by booting from a CD-ROM. You can predict the probability of this by observing the way your computer boots. In this nonfunctioning mode, if the drive light goes on and then off — as if the computer is trying to find something in there — you may have a chance. If the light doesn’t come on, however, you’re probably out of luck.
During the recovery process, it’s critical to download the correct file from your motherboard manufacturer or from AMI (American Megatrends Inc.), since there are many flavors of motherboards and AMI is custom-making the BIOS software. There is a BIOS identification guide on AMI’s Web site.
Once the file is identified and downloaded, rename the file to the name AMIBOOT.ROM and place it on a blank CD. The media does not need to be bootable for this to work.
Insert the floppy or CD in the computer and reboot while holding the CTRL+HOME keys. If everything’s going according to plan, your BIOS should update.
Be patient, as this process can take a few minutes. When it’s done, you should hear four beeps. Then, remove the floppy or CD and reboot.
If the procedure outlined above didn’t work, you may either need to replace the motherboard or the BIOS component, if it’s a BIOS that can be removed. 8
Avner Izhar, CCIE, CCVP, CCSI, is a consulting system engineer at World Wide Technology Inc., a leading systems integrator providing technology and supply chain solutions. He can be reached at firstname.lastname@example.org.