Find the datasheet for that chip and check what voltage it is, probably 5V. Find another chip and compare datasheets: is the voltage the same and is the pinout the same. You don't need to have exact same chip, but it needs to be programmed before you use it. Sometimes you can even use larger chip, but you need to flash multiple copies of BIOS so it fills the entire space.

I've noticed that 29EE010 chips work well with most Pentium/Pentium II motherboards.

BTW how will you flash the new chip? If you don't have external programmer it is theoretically possible to hot swap chips after you boot into flash utility. But there is risk of damaging stuff.

adalbert wrote on 2020-07-15, 20:26:

BTW how will you flash the new chip? If you don't have external programmer it is theoretically possible to hot swap chips after you boot into flash utility. But there is risk of damaging stuff.

Thanks everyone for the replies.

I plan on using UNIBIOS since I can still boot from a floppy. The motherboard has the bootblock bios, and by using a fake modified version of AWDFLASH I could boot to a command prompt. But as per your response I understood I need the exact same chip to be able to do that, other brands will require me to flash it somewhere else before plugging it in.

I also have another motherboard, a V72MA which also uses an 2MBIT DIP32 chip. I though about canibalizing its chip in order to restore the 7KXA (i.e forcing it to flash the 7KXA bios into its own chip), but I really don't want risk having two broken motherboards instead of one.

gaffa2002 wrote on 2020-07-15, 20:33:

I plan on using UNIBIOS since I can still boot from a floppy. The motherboard has the bootblock bios, and by using a fake modified version of AWDFLASH I could boot to a command prompt. But as per adalbert response I understood I need the exact same chip to be able to do that, other brands will require me to flash it somewhere else before plugging it in.

Even the same chip could have different BIOS flashed or be empty, so the model doesn't matter. If that motherboard has functionality of booting from floppy with BIOS chip removed (I don't know if that's even possible) you might be able to flash any chip. But if it's not possible, then you need to find a way to flash new chip. This is what I did some time ago:

- original BIOS chip is in motherboard
- I booted from floppy into flash utility
- I removed BIOS chip while computer was working (that's the dangerous part)
- inserted new BIOS chip (it was a different model)
- flashed it

it's best to do that on a spare motherboard which is not valuable. In theory you could flash any BIOS on any motherboard and replace the chips afterwards.

adalbert wrote on 2020-07-15, 20:50:

Even the same chip could have different BIOS flashed or be empty, so the model doesn't matter. If that motherboard has functiona […]
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gaffa2002 wrote on 2020-07-15, 20:33:

I plan on using UNIBIOS since I can still boot from a floppy. The motherboard has the bootblock bios, and by using a fake modified version of AWDFLASH I could boot to a command prompt. But as per adalbert response I understood I need the exact same chip to be able to do that, other brands will require me to flash it somewhere else before plugging it in.

Even the same chip could have different BIOS flashed or be empty, so the model doesn't matter. If that motherboard has functionality of booting from floppy with BIOS chip removed (I don't know if that's even possible) you might be able to flash any chip. But if it's not possible, then you need to find a way to flash new chip. This is what I did some time ago:

- original BIOS chip is in motherboard
- I booted from floppy into flash utility
- I removed BIOS chip while computer was working (that's the dangerous part)
- inserted new BIOS chip (it was a different model)
- flashed it

it's best to do that on a spare motherboard which is not valuable. In theory you could flash any BIOS on any motherboard and replace the chips afterwards.

Just tried the hot-swap method you suggested on the V72MA using the EP-7KXA chip which I assumed was broken, and the flashing WORKED! Issue was on the flashing process and not on the chip apparently, both motherboards survived and now everything is booting fine. My Windows 98 machine is finally back from the dead 😀,
Thank you so much for the suggestion!

That's a great news, I'm glad it's working 😀