CPU Temps are driving me out of my mind

[flauntyham]

Okay, here's the deal.

After reading and rereading Computronix's C2D Temperature Guide, I am utterly confused about the readings I'm getting as I try to calibrate Speedfan. I'll try to include all pertinent information.

CPU: E6600 B2 Stepping
Zalman 9500 cooler
Ambient Temp measured at the front intake: 20C
All fans on high
Vcore: 1.28? or whatever the lowest available in BIOS
FSB: 178
178 X 9 multi = 1.6 GHz cpu speed

Now, my confusion.

Both CoreTemp and DTS readings using Crystal CPUID MSR Editor indicate idle temps for Core 0 to be 17-18C and Core 1 to be 22-23C. When calculating temps using MSR Editor I am subtracting the register values from 85C as that is the Tj Max according to The Guide. That is, at idle the register values are consistent with CoreTemp's readings which are also based on a TjMax of 85C.

How can this be? If ambient temps are ~20C, how on earth can Temps derived from DTS readings as measured by CoreTemp and Crystal CPUID be less than ambient. Two things come to mind. One is that I am a complete numbskull and fail to understand temps and Computronix's Temp Guide, or Tjunction Max is actually 100C despite what The Guide says.

What the heck am I missing?

If someone is able to explain this, I will be truly be indebted. Thanks.

 

[CompuTronix]

flauntyham, sorry you're having difficulties. You're not missing anything. The B2 Stepping Conroe's are indeed Tj Max 85c, however, it appears that your particular processor is mis-calibrated from manufacturing to Tj Max 100c, just as you suspect. Intel doesn't always get it right, so mis-calibration problems do occur occasionally among various processors.

I've seen DTS mis-calibrations which were more than 5c below ambient at Idle, as well as 39c above ambient at Idle, and ran just fine under Load. I recommend that you configure SpeedFan Offstes to compensate, so that your temperatures are similar to the following while under the Idle Test Setup:

Ambient = 20c
Tcase = 21c
Tjunction = 36c Hottest Core

Tcase to Tjunction Delta = 15c +/- 3c

Remember to adhere to Core Offsets in 15c increments. If you deviate from this value, then your Core temperatures will be inaccurate.

Comp

 

[flauntyham]

Hey Comp,

Thanks for the response and the reassurance. I'm glad that I was thinking about this correctly as I'm really hoping to acheive accurate temp readings. I will follow your advice and maintain the 15c Tcase to Tjunction Delta. Thanks again for your help, I sincerely appeciate it. And thanks for The Guide.