955 c3 core 4 crashing

when I start running prime95 my fourth core stops working after a min. The rest of the program runs and the computer doesnt crash or anything, but if I load up the comp core 4 crashes. Ive tried running folding and core 4 stays active with that...weird.

I stepped it up so Im running at 4ghz with htt and nb @ 2600. my temps when loaded are 50-51c. I oc through bios but ill use amd overdrive cause its got all the info you need in one screen shot. Did i get a messed up cpu or is that htt/nb speed too high?

EDIT: I reseated my cooler and my temps dropped to 47-48c...much better, still crashes core 4 though

So I went to get more screen shots to show the core crashing, my temps and my settings and now I cant get it to crash again. Is oc'ing a new cpu right of of the box a nono? It passed prime95 now for a couple hours, no errors..i am confused

A lot of people like to "break in" their CPU before OC'ing it. I think it's more the HS and TIM settling in than anything else - and who knows for sure ...?

Cores ending usually means your not giving it enough voltage to the CPU. The thing is that you don't need to give to much for 4.0ghz with the C3 steppings.

ya i have it down to 1.45 right now, down from 1.5something. Its stable, but if i step up to 4.1 or 4.2 it crashes after i 100% load up the cpu. Ill have to mess with it a bit. my goal was 4.0 on air, but that was pretty easy to reach, maybe 4.2 now if it will go that high