IDE, RAID, or ACHI

Clint, I’m wondering if your reply has anything to do with what I’m seeing. I just upgraded to a new Gigabyte mobo and 500Gb SATA-3 Caviar Black that, for some reason, I can’t get to work as AHCI in the BIOS. It hangs on boot. I need to drop back to Native IDE to get it to work, which means I’m not getting the speed from the drive I should.

System is Win Xp Pro. What’s the driver I need, is it an Xp driver, and where can I get it? Any help would be appreciated.