If it makes you feel any better my P4C 2.8 @ 3.2 was running @ 90C b/c i accidentally put too much ceramique on it!
Did you put any sort of thermal compound on it? If so then check to make sure you didn't put too much. Also check to make sure you removed the plastic film off the bottom of the heatsink!!!! [very important]
Lastly if you did put thermal compound of your own on remove the thermal PAD that came with the stock heatsink.
Hope this helps