AMI BIOS CORRUPTED BY CHERNOBYL VIRUS-HELP!

[jordo]

I have a K7SOM+ 7.5C mobo with an AMI BIOS chip soldered on it. All other perpherals are onboard (except NIC and modem). I recently got hit by Chernobyl virus (W95.CIH) and my computer went dead immediately after trying to clean it using Norton Antivirus and rebooting. Everything seems to start OK with the processor fan starting and all the other LEDs lighting up OK. But there is no video-the screen is blank. The computer beeps once when I turn on power as if POST was successful but then the floppy drive light comes on and the drive tries continuously to access a diskette. I figured BIOS was flashed and was attempting a boot block recovery. So I tried the boot block recovery method for AMI chips using a MSDOS formatted diskette with the AMIBOOT.ROM file which I had obtained from the manufacturer's website (www.ecsusa.com) and tried to boot with it. But it did not work. It just beeps after every 7 seconds after it has tried to access the diskette and presumably fails to find the AMIBOOT.ROM file. I cant hot flash since my chip is soldered on.
Is this a BIOS problem or am I barking up the wrong tree? If so could Chernobyl be responsible? Can I rescue my mobo?

I do not know what else to do and would appreciate any help you can offer.

[ajzchips]

Is the AMIBOOT.ROM file the ONLY file in the non-bootable formatted diskette? It should be.

Try downloading another BIOS file and try renaming it yourself to AMIBOOT.ROM

[NickS]

Try clearing CMOS. I doubt this will help, but "any port in a storm".

I would be a little surprised if the BIOS chip has gone faulty but this is a possible cause of the BIOS recovery procedure failing. The other is that the boot block has been corrupted.

Is the BIOS chip the one shown in a socket by the power connector, with a label, in this picture?
http://www.hw.by/images/K7SOM/board.jpg
(warning: 200KB)

[jordo]

Thanks for the fast response guys.
Ive downloaded the BIOS ROM file from ECS site and renamed it myself. I copied it to the diskette immediately after a full format. I even copied a ROM file from a similar mobo and renamed it on a formatted diskette and nothing changed. Cleared CMOS too but that doesnt help either.

Sorry NickS. The mobo in your pic is a K7SOM which I believe has a PLCC BIOS chip that can be readily removed and replaced from its plastic carrier. My board is a K7SOM+ with everything soldered onto the board including the processor.

Check out this pic for my mobo. The BIOS chip is at the bottom left corner of the board. (Sorry its not very clear)
I thought the ROM part of the BIOS which attempts recovery could not be corrupted. Is it possible to easily overwrite it. Ill appreciate any further suggestions.

[Ritchie]

I'm not sure if I would have been as quick to try bootblock recovery, without knowing for sure whether the BIOS was corrupted or not. Possibly if the BIOS was previously OK you may have added to the problem by attempting the bootblock recovery.

What I would suggest is disconnecting the hard drive completely and seeing if you get a display. I don't know if the result of this would be any different to before you attempted bootblock recovery.

[jordo]

Thanks Ritchie.
Actually at first I did not even suspect that it was a BIOS error. I did not even know about bootblock recovery! I tried all standard troubleshooting by disconnecting drives and PCI devices, reseating memory the works -and still nothing changed...thats when I reckoned it must be BIOS failure and attempted boot block recovery afterwards.

[Ritchie]

I'm glad you tried all the regular troubleshooting first.

Looking at your original post again it seems the problem developed as you tried to deal with a virus, which means the virus probably infected or corrupted the BIOS.

Which means that your efforts to recover the BIOS via bootblock recovery are probably still the best way to go.

Alternatively, if you have a spare BIOS chip that you could flash on another machine, you could try to get the PC operational using that chip first/instead. (Flash the correct BIOS using another machine and then transfer it into this problem machine).

[Ritchie]

I think the last time I did this was using a bootable floppy.

However, cannot remember whether I copied AWDFLASH.EXE over COMMAND.COM or kept both COMMAND.COM and AWDFLASH.EXE.

I remember having a bootdisk with the automated flash command (ie: A:\AWDFLASH.EXE NEW.BIN /PY /R).

This is what worked for me. If I knew where the sucessful bootdisk was I would take a look and tell you exactly how I had it setup.

I realise you are using an AMIBIOS. Subsitute the flash software where appropriate. And also, I don't see any reason why you should not be able to use UniFlash for the bootblock recovery attempt.

[NickS]

I thought the ROM part of the BIOS which attempts recovery could not be corrupted. Is it possible to easily overwrite it. Ill appreciate any further suggestions.

Unfortunately, in many cases it can; some flash EEPROM devices have a protected bootblock area that can only be written to after "unlocking" by a series of writes to a specific location (which of course could be carried out by a virus) but others are pretty open. I still prefer the jumper method of protecting old-style flash devices, also putting devices in sockets (derided by Tom's Hardware who obviously have not had a BIOS flash go wrong).

Are you pressing Ctrl and Home together to get the floppy disk drive to read the disk? Or does it just do this on power-up anyway?

[jordo]

Thanks again guys.

Ive tried pressing Ctrl+Home when powering up but again theres no change. I dont even need to press the keys.....the recovery process initiates itself on powering up. I suspect at his point that perhaps the ROM part of the BIOS chip is corrupt.