Make sure u disable "Automatic QFan Control" in the bios .. or any target temp that u might have set ...
Also , the voltage can fluctuate when set to auto .. for a CPU running at stock .. i'd recommend u to try some permanent voltage between 1.2 and 1.25 ... u don't need anything more for a C2D at stock .. i'm running mine oc'ed at 3.02 GHz with only 1.25V

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