BIOS Updates forum

My Pm29F002T - 12PC chip seems to be physically defective. I used it in MOBO Biostar M7VKB It gave me the message "BIOS ROM checksum error" I had to boot from floppy using the BootBlock, then I flashed the BIOS but after restart, I got the same message. I think I need to replace the chip. I cannot find this particular chip in local shops. Is there any wrong when I purchase a different 256 kB chip and hot flash it? Can I use any kind of 256 kB chip? Whats the difference between 256 kB FLASH chips?
Thanx for help

If the chip flashed OK, then it's OK. Maybe you have bad CPU or bad memory.

[quote="Rainbow"]If the chip flashed OK, then it's OK. Maybe you have bad CPU or bad memory.[/quote]

You're probably right with the chip being OK as I have successfully flashed it with Uniflash on another computer. I am sure about my memory as well. I have tried all three modules I have on another machine and all are OK. I only wonder, is it possible that with a deffective CPU I am able to see anything on display and even to control IOs?

BIOS checksum error is often caused by bad CPU or bad CPU cooling, especially with AMD CPUs. The CPU partially works, but is not able to compute the checksum correctly (or the checksum of BIOS decompressed into memory is bad because of bad memory).

BTW.: What board (manufacturer, model, chipset) have you used to flash the chip? I would like to include it in UniFlash documentation

I have used Luckytech's 5MVP4 board (Socket 7) - chipset VIA MVP4. I used the Uniflash to write BIOS incl. the Boot Block to the chip.

Is there a way I can find out whether my CPU is bad other than trying to plug it into someone elses mainboard? I mean a small test program I can run from the boot floppy...

I don't think so. The bootblock BIOS is very limited - it can read initialize graphics, read from floppy and read from keyboard, so many programs will not work.

I have bought a new CPU - Duron 950 and everything is OK. Thank you for your advice.