Hi, I am trying to flash an Asus HD 5770 EAH5770 CuCore2DI1GD5. I have flashed many Nvidea cards and Mobo bios's but I am stuck with this card. I am not trying to switch sub vendors or anything remotely tricky, just flash the card with a slightly earlier bios. The original bios on the card is this one.. http://www.techpowerup.com/vgabios/77871/asus-hd5770-10... (March 2010) I would like to, but have failed in, flashing with these.. http://www.techpowerup.com/vgabios/68521/asus-hd5770-10... (Jan 2010) http://www.techpowerup.com/vgabios/69307/asus-hd5770-10... (Sept 2009) According to ATIFLASH I have no problem flashing successfully with these bios's but they just brick the card? The failure is in the form of the the Mob failing to post at post code 2b (initialise VGA bios). Just hangs right there. If I flash back to the original bios, no issue, so theoretically ATIFLASH is working correctly and I am completing the process without error. Am I missing some thing here? Any thoughts please? Thank you. Edit. looking closely at the bios Internals info I notice that March 2010 has this description.. GPU Device Id: 0x1002 0x68B8 113-AC37500-104 68B188.8.131.52.4.AS02.U126 And Jan 2010 has this description.. GPU Device Id: 0x1002 0x68B8 113-AC37500-101 68B184.108.40.206.0.AS02 Noticing the .U126, wondering if that suffix is relevant ??