CPU temperature rises when you start windows. Booting windows and loading startup programs is very cpu intensive. To make it worse, some systems hand off control of the fans to the OS during boot, so the temperature sometimes spikes 30-40 degrees for a few seconds in some cases, but there's nothing to worry about.
My Q9650 & a E8400 I have both show something wierd with CoreTemp at idles.
But perfectly fine once under a load.
The Quad has Core 3 stuck at 40C no matter what, when in reality its in the low-mid 30s.
The other 3 seem to be fine.
The E8400 has core 1 stuck.
It does seem that idle temps are just a rough guideline and often inaccurate.
I honestly wouldn't worry to much about them.
Since its more accurate under load:
Run Prime95 for a couple hours.
At that point, make note of what the Temps are.
If they are reasonable, I wouldnt worry about what it shows at idle as theres a very good probablity that at least 1 of the cores is not being reported properly when its idling.
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