Hmm.. data corruption, I hate that. No way I would risk it yet until something is sorted out or more clear about this. MEM instability can easily screw up a Windows install though, and so can unstable FSBs. I've had it on many boards, not just the 790i you're seeing it now, I experienced it on my P35 about 6 weeks ago, "system32 is corrupt or missing" on reboot after trying 475FSB with an E8400.

cognoscenti: he's kidding but trying to say something at the same time
Have you tried 8-8-8 MEM settings?