Try and see. You already 'bricked' the system, so you don't exactly have much to lose. No luck? Grab any other suitably-sized EEPROM (2Mb by the look of it) and use that instead.

dionb wrote on 2021-01-19, 21:15:

Try and see. You already 'bricked' the system, so you don't exactly have much to lose. No luck? Grab any other suitably-sized EEPROM (2Mb by the look of it) and use that instead.

I think it might be hard to find a suitable replacement which is pin compatible and has the same functionality. The chip is not just an EEPROM as I understand it from the datasheet.

Found this site offering flashed replacements, might be my best option perhaps.. http://www.chip-service.de/product_info.php?l … C%20Ersatz.html

Most boards from this era can read from winbond W29c010 chips. Maybe that one is even pin compatible with that chip ? Try to read from it by unchecking the "check id" option in xgpro and see. If not you can buy one for cheap and I'm pretty sure that'll work.

Deksor wrote on 2021-01-19, 23:14:

Most boards from this era can read from winbond W29c010 chips. Maybe that one is even pin compatible with that chip ? Try to read from it by unchecking the "check id" option in xgpro and see. If not you can buy one for cheap and I'm pretty sure that'll work.

Wouldn't it need to be a W29c020 if the BIOS is as large as the existing chip?

True, I don't know exactly how large is his chip.

guzzard wrote on 2021-01-19, 22:18:

dionb wrote on 2021-01-19, 21:15:

Try and see. You already 'bricked' the system, so you don't exactly have much to lose. No luck? Grab any other suitably-sized EEPROM (2Mb by the look of it) and use that instead.

I think it might be hard to find a suitable replacement which is pin compatible and has the same functionality. The chip is not just an EEPROM as I understand it from the datasheet.

Found this site offering flashed replacements, might be my best option perhaps.. http://www.chip-service.de/product_info.php?l … C%20Ersatz.html

The datasheet refers to much older system architecture than the BX board you have. Also never seen Soyo use weird stuff like this. I'd expect it to use some regular Atmel/Winbond chip.

Quite possibly the odd architecture of the EEPROM is the problem, the reason why the existing one failed. Once again, you have nothing to lose - that EEPROM isn't going to boot anything in its current state.

Not many pictures of that board, but this one seems to be fitted with a standard dip32 EEPROM although the footprint on the board is for a dip40. Maybe worth a try, but there could be one or more jumpers/wire links to be configured for switching between the two.

dionb wrote on 2021-01-20, 00:15:

The datasheet refers to much older system architecture than the BX board you have. Also never seen Soyo use weird stuff like this. I'd expect it to use some regular Atmel/Winbond chip.

Quite possibly the odd architecture of the EEPROM is the problem, the reason why the existing one failed. Once again, you have nothing to lose - that EEPROM isn't going to boot anything in its current state.

quicknick wrote on 2021-01-20, 11:55:

Not many pictures of that board, but this one seems to be fitted with a standard dip32 EEPROM although the footprint on the board is for a dip40. Maybe worth a try, but there could be one or more jumpers/wire links to be configured for switching between the two.

Thank you both @diob and @quicknick!

I did a bit of digging on eBay for pictures and it sure looks like you are on to something. Looks like it might be possible to use a DIP32 EEPROM. I think the board is compatible with both, hopefully without changing any of the surrounding circuitry. On the pcs the model number for the current chip I have is printed under the socket, see attached picture. Hopefully the model name of the DIP32-chip is also printed underneath. I will check asap, have to get the motherboard from storage which will take a day or two.

The soldered jumper on the left is in a different position.
Maybe that´s to enable different EEPROMs or maybe it´s just a different mainboard revision.

I have two SS7 boards from Soyo, both use Macronix MX28F1000 flash chips. In the photo that I posted the Macronix logo is visible, so probably a MX28F2000 if the bios image is 256KB. Was tempted to say that any 2mbit flash should work, but boards from that era often needed to write to the flash chip (ESCD or DMI data, I'm not so sure) so the chip needs to be compatible with the board otherwise a message along the lines of 'unknown flash chip' will greet you upon applying power.

majestyk wrote:

The soldered jumper on the left is in a different position.

That^. And there could be differences in the passives soldered to the left of the chip (those below seem identical, although it's hard to tell for sure since the picture is so poor). If you find a still-active sale, maybe kindly ask the owner to provide a close-up of the area?