You might be right. I have been try to fix things and forgot to check which mode I was in. Anyway, I re-installed yet again and chose RAID so later I can switch to AHCI or IDE. However, I downloaded the back2awd as suggested (actually efi2awd downloaded here http://forums.tweaktown.com/attachm...3261131-gigabyte-latest-beta-bios-efi2awd.zip) AND I swapped RAM module to make sure it's not RAM problem and redownloaded firmware F10 to F13, boot into DOS, ran efi2awd with 4 different BIOS, and efi2awd complained that all of them are Bad BIOS Images! I'm really giving up. Need to contact Gigabyte.