Hmmm... it looks like Core#3 is getting awful hot (98C?).
You should perhaps use Prime95 to see what all 4 cores will get up to. Either somethings going on with the DTS sensor, or if you are using the stock HSF, you might have one pin not secure on the 4 pin HSF.
Hard to say.
Edit:
You can find the Prime95 update from this link:
How to Overclock Quads
Basically you install the original software and replace the EXE file to update it. The update has the 32bit, and there is also a newer version for 64bit. Hard to tell what OS your using, even though looks like vista.