I have a Q9300 which I purchased in an HP system in 2008. Last January I got rid of the HP but kept the processor. It is now in an AsRock P43DE MB. I never checked the temp of the CPU when it was in the HP system but it has been running very hot since I started checking it on the new system.
Currently it idles around 45-50C. Stress testing with Prime95 the temp doesn't increase as much as I would expect either though. At full load it will only get to around 60C.
I bought a Corsair H50 unit when I built the new system and am using two aftermarket fans in a push pull setup. I am also using Artic Silver thermal compound. I first installed the system, waited 2 weeks to see if the temps would drop. After the temps didn't drop, I took the heatsink off, removed the thermal compound, and installed from scratch. I have done this 3 subsequent times and have the same result each time. I am also pretty sure I am not using to much or to little thermal compound. I have tried slightly different amounts of the thermal compound, again with the same result.
The system works fine so it isn't a big issue but I don't understand why I can't get the temp to drop.
Here is the rest of the system:
Case: Antec 300
PSU: 520W Seasonic
MB: AsRock P43DE
System Drive: OCZ Vertex 2 120GB
HDD: 3 x 2TB WD Caviar Green
RAM: Generic 4GB DDR2 from HP
GPU: GeForce 9300
OS: Win7 Home Premium
FYI: I did put the H50 on another system of my brothers to check if it was working correctly, and it worked great on his system. He has an i7-920 and it kept it at around 25-30C idle and loaded to around 45-55C.
What software are you using to check the temps? I only ask because I would think that stress testing would increase temps more than that also. You should be using REALTEMP or OCCT and you can also use it to do some stress testing and watch the temps at the same time.
Probably not, but at those temps it wouldn't hurt to see what you get. I just thew them in incase you were using some "never heard of before" temp monitoring program that might have been giving you skewed results.