i was using and im still using same system as your's . p4 3.0ghz on D101.
i face the same problem in the past. i solve my problem doing these steps :
1. Un-Attached all Things Relative to Mobo like ram,cables,procy,heatsinks,cards.
2. Remove all components from Casing (mobo, psu , HD etc)
3. Use Bloor/blur/blour (its a Air Machine) to Remove all Dust from Casing , PRocy Heatsink, PSU.
4. Cleanup all my Hardware mobo, cards , psu , heatsinks again with Paint brush and Tootbrush.
5. Re-Assemble again the whole system.
NOW THE RESULTS :
Temps of Procy = 70'C (before this cleaning it was 100+C )
what da F***kkkk ?? :X
then i finally saw "there are four plastic screws of Heatsink of the Processor , 1 of them are Loose".
i Fixed it and i maKe sure that Heatsink is very very closed to Procy by pushing Screws Tightly too the Motherboard.
Now The Results Are :
54'C Ideal & 91'C on 101% Stress . (tested by many softwares)
Note: im using this Processor "Without" any Kind of Thermal Paste*. so its Quite Good.