After reading this great guide on how to get your true temps for C2D/Q I noticed many Tjunction Max* that were listed were not matching that of CoreTemp. You may be getting core temp readings 15c LOWER than the true temp. As of CoreTemp 0.95.4 many C2D processors have their Tjunction Max in CoreTemp read as 85c when it is indeed 100c**. I have verified myself that E4x00 series have a Tjunction Max of 100c because I pushed my cores to a max of 92c it did not shutdown or throttle (those that didn't know Tj Max is the shutdown temp of a C2D/Q processor and they will thermal throttle 5c below Tj Max, so current Core 2's throttle at 80c and 95c respectively).
These are the proper listings of Tjunction Max on current Core 2's, this list was pulled from the guide I gave a link to above.
100c Tjunction Max
-E21x0 L2 and M0 stepping
-E4x00 L2 and M0 stepping
-E6x00 L2 stepping ONLY
-E6x50 G0 stepping
-E6540 G0 stepping
-Q6x00 B3 and G0 stepping
-QX6x50 G0 stepping
-QX6700 B3 stepping
85c Tjunction Max
-E6x00 B2 stepping ONLY
-E6x20 B2 stepping
-X6800 B2 stepping
Untill an updated CoreTemp is released do NOT go by what CoreTemp says untill you check back here at OCN. Some people say Tjunction Max is moot but that is not true, many users including myself might of been running a Tjunction Max 100c processor and believing the temps CoreTemp reports which are indeed 15c TOO LOW. Remember Intel's thermal spec is based on Tcase not core temps. Currently all G0, M0 and B3 steppings of chips have a 10c delta between Tcase and Tjunction (Tj = core temps), while B2 and L2 stepping chips have a delta of 15c. You will notice on average the delta can range between 7c - 13c depending on the chip's speed and vcore, sometimes it can exceed 15c delta which is ok once you know your temps are all calibrated properly (refer to the guide above on how to calibrate).
*Tjunction Max or Tj Max is the temp your CPU will shutdown at. 85c Tj Max CPUs will shutdown if core temps reach 85c and 100c for 100c Tj Max CPUs. When core temps are 5c below Tj Max thermal throttling will occur which will drop vcore and CPU speed in attempt to cool down the CPU. Tj Max 85c will throttle at 80c and Tj Max 100c will throttle at 95c.
**This also applies to Speedfan 4.34 beta 36, Speedfan and CoreTemp are using the same detection method, so the processors that have a misread Tj Max in CoreTemp WILL have the same misread in Speedfan.
I hope this will help clear up many of those wondering why your temps seem strange. Whatever processor you have, if Coretemp reads it as 100c Tj Max it should be accurate, if it reads Tj Max as 85c you better check back to this thread or the full C2D/Q temp guide and look up your CPU and stepping, CoreTemp may be wrong as it was with my M0 E4500.
EDIT: CoreTemp shows Tjunction Max as just Tjuction, it is not displayed properly and should be shown as Tjunction Max. Hopefully this will be corrected in the next version.
