Sometimes the chipbed is uneven on a mobo, or the retention bracket/spring will cause the chip to not sit flush w/ your heatsink.
Most of the time, the heatsink is drenched in thermal paste so it's not that serious of an issue.
You however, seem to understand how thermal paste is supposed to be applied so keep in mind a pea sized amount is going to require more attention to subtle details.
Grab a piece of carbon paper and mount your heatsink. Take off the heatsink and examine the carbon paper to see where contact is not being made. Grab some sandpaper and lap accordingly.
The D's do run a bit hot but 40c (idle) if not less should be acheivable with a better CPU cooler.
Also, check if there is a mobo update and google the mobo to see if others report high temps as well. The Abit IS-7's for example, generally report higher than actual CPU temps.
This post has been edited by LiquidSage: 08 March 2006 - 07:11 AM