Good point some detail may help:

Im running Crucial Ballistic tracers which pass memtest hands down at 1200 mhz 5-5-5-10 at 2.25 and 2gb's I havent tried running a stability on 4gb because im running below 1033 ...

I was running my 2 74gig raptors in Raid 0 just fine until going from Vista 32 and 2 gbs of ram to Vista x64 and 4gbs.

My OC is at 4.3 ghz under SS and -45c and my bios is 0402.

Im a little surprised at my current problems but am not throwing in the towel just yet.