There's no such thing as 'generic' EEPROMs. Check exactly which chips you have, what their specs/pinout are and see if the replacement is compatible (at least read compatible, if you're flashing on the TL866 it doesn't matter if your board can't flash them as it expects).

Thanks, I am quite a noob in this so thanks for the patience.

The original bios is a 1 Mbit 32 pin dip eeprom. I was thinking of dropping in whatever 32 pin dip eeprom I could find available. Am I to understand this would not work? If hotflashing works, I was thinking that any 32 pin dip eeprom (same pinout, of course) would work, regardless of brand.

mihai wrote on 2021-08-31, 19:26:

Thanks, I am quite a noob in this so thanks for the patience.

The original bios is a 1 Mbit 32 pin dip eeprom.

Yes, but which vendor and model? it's generally written on the top of the EEPROM.

Something like "Winbond 29C010".

Once you have that, look up its datasheet (google the vendor + model name + "datasheet"), then compare that to the datasheet of the replacement.

Check:
- pinout
- internal organization
-read voltage
- write voltage

Most EEPROM-era EEPROMs are similar and pretty interchangeable, but not all.

Thanks. I bought a programmer and will start experimenting soon.

ok, so started playing and patching bioses. my findings:

1 - I could not find many stocked DIP32 eeproms with mouser / tme.
2 - most I could find are on ebay.
3 - killed a motherboard by flashing a patched bios; I have reflashed it again using TL866 (and the appropriate chip). The bios and the board are back to life, BUT, at after each and every cold boot I get "checksum error" (weirdly enough, cold boot only); I changed the coin battery, same issue. Quite strange, not sure what the problem is, unless I did something to the bios chip when flashing it in the programmer. Any ideas appreciated.

4 - played extensively with BIOS patcher, to fix HDD recognition issues for >32GB. Not quite succesful:
- patched bioses do not recognize the CPU when PS2 keyboard / mouse is plugged in.
- patched bioses DO recognize the >32GB hdds, but hang with detecting other IDE channels.
- conclusion: not satisfactory.

5 - on a separate note, tried inline programming the 93C46 eeprom on an audigy - no luck, "over current protection" errors. Tried also rotating the pins - no luck again. My definitive conclusion is not the 93C46 eeprom on an audigy 1 cannot be fixed inline.

final results. I bought 3 random bios chips from ebay; I did not care about brand / technical details, I just checked to be 2Mbit and to be programmable with 5V.

I have programmed the new bios chips with TL866 and dropped the new chips in the mobos with defective bios chips: 100% success rate, ie 3 out 3 are working, BIOS settings are saved and survive cold reboots, ESCD updates are fine. The initial bioses were ST / MX / ATMEL eeproms, the replacements were almost all SST eeproms.

Indeed, I cannot use awdflash to flash the new bios - no issue there.