For the L2 processors the competition uses TjMax=100C while RealTemp uses TjMax=85C so when uncorrected, there will be a difference of 15C.

kaltblut: Have you ever tried running my test where you drop your processor down to about 6x266MHz or 6x200MHz and drop the core voltage to about 1.10 volts if possible. Show us your idle temps compared to your room temperature with zero calibration and I think it will be pretty obvious what your real TjMax is. Most L2 processors when using TjMax=85C will report an idle temperature during this test a couple of degrees below the room temperature.

This is impossible so CoreTemp and others decided a good fix would be to boost TjMax up to 100C. That covered up the inaccurate sensor issues at idle but now these programs report load temps that are 15C higher than the actual temperature. Read the docs to learn more about this issue:

http://www.techpowerup.com/realtemp/docs.php