Perhaps try to flash the card and force the "flashtype" parameter (at your own risk, especially when you don't have the backup of the original bios anymore, so it may not work with the bioses from older revision videocards):
From the picture you posted earlier you can see that the flashtype is M25P10/c and that's STMicroelectronics. Perhaps try:
atiflash -st -f -p 0 bios.rom
or if atiflash didn't work out, then try out Flashrom:
Flashrom -p -st 0 bios.rom -f
If it still doesn't work, then the only solution would be rma, otherwise you need to buy a new videocard.