Have you set your memory to 166mhz instead of 200 ? else they'll be oc'ed as well.
My opty 170 runs at 2.65 with memory at 166 (220 effective) - higher fsb means memory needs to go down to 133 to not turn unstable. Perhaps you've forgotten the memory setting? You could also try changing to cl3 in the bios?
What's the fsb running at? and did you try lowering the HT link to 600 (mine runs 1050mhz flawless, but who knows)
What does cpu-z tell you the memory runs at ? (www.cpuid.com)
and how do you test it's stable? do you just OC it and start playing games etc? (if it ain't stable, it can fuck up your filesystem and other stuff before it fucks up enough to get a debugcheck (the blue screen).
if your cpu and/or memory is making errors, it can invalidate memory, and therefore write wrong data to disk or programs, and/or cause unexpected crashes. For instance it can set invalid return addresses at the end of a program sequence, causing it to jump to invalid code (similar to bufferoverflows).
In any event, make sure you stress the system when you think it's stable.
Perhaps check the other thread I posted in earlier for some tips.
Have have you turned down the the hyper transport bus? Probably not a power problem, unless you psu is having it's issues. It should have enough power, as my system, similar to your with sli 7800gtx's oced, and the 165 @ 3ghz would draw 330w from the wall under load.
I think you are missing a setting or two. Loosen up the ram timing, turn the ram down, lower the HTT bus.... etc.
Well by testing it I just do some browsing for a bit and go from there. CPU-Z says 200 for the RAM as well. Once I get my new stick of ram back, I will put it down to 166 and do what you said in your other thread to see if I can boost it up. Thanks!
Well even though my PS is 420w it is one that came with my antec case going back about 4 years. I think it is an antec PS but not 100% sure but I have never had any issues with it so far. Could it be the ps though and it is not strong enough?