i have an e8500 and i have a difference of 10C between the cores. it seems that some of the 45nm intel processors have really bad temperature sensors.
i've seen some people who only have 2-3C difference between cores and others like me who have 10-11C. i was planning on returning my e8500 to intel for an exchange but i think they'll probably just send me a refurbished unit, so i think i'll stick with the one i have.
Until Intel explains how the Tjuction works, perhaps then you might have a better understanding why the cores are reporting different temp, since those are based Tjmax temp.
Its better to use the programs that read cores for load temps rather idle.
I've noticed that my E4400 on load will be the same or off by 1 degree.
On my Q6600 2 of my cores are 2C cooler then the other 2 when under load.
Again those are based on a Tjmax. And since I've switched MB, my DFI is acting different the my P6N in reporting core temps. The difference is the same on the cores (2C cooler), but the Tcase temps are different. One difference though, is my old P6N didn't have Thermal Management Control option.
So what is the most accurate temp reading program? I found something through a google search showing how to make changes to speedfan, which I did. Thats how I got it to align exactly with Real Temp 2.70.. So I thought I had nailed it...
I just realized something... 2 are showing my temps at 25c and 34c,(speedfan and Real Temp) and core temp and HWMonitor show 10c higher...
And 25c would make it roughly 77degree.... I keep the thermostate at 72f.....I dont see an e8400 OC'd to 3.8Ghz with a vcore of 1.2635 (vid is 1.225) running 5f degrees over ambient... or I have one awesome little cpu....
Again.. the tjmax are different for all those temp apps, and that is why you get different readings. The Tjmax is not sensed by any of those apps, or anything that displays core temps. Look at where you have the program CoreTemp. It should have an ini file. You can manually change it.
Try putting -5 where it says tjmax offset. It should read the same as RealTemp, for 95C tjmax.