Intel TAT / CoreTemp / IDCC all different temperatures....

[SLi_dog]

The general assumption that DTS=20 or 65C is a good number to shoot for when overclocking is too vague. 65C is an undocumented absolute temperature and people's definition of overclocking varies. My E6400 runs fine at 80C (DTS=5) when overclocked to 3200 MHz but 60C (DTS=25) is a good upper limit when I'm pushing it to 3600 MHz and a little beyond, God willing.

It may appear to be more vague that it really is. By definition, running your CPU no closer than 20C from the DTS 0C point means exactly that. You'd have to factor in maximum CPU load and maximum ambient operating temperatures into that threshold. eg, don't go setting the 20C DTS rule as an idle temp at 6am in the middle of winter

I kinda threw it out there as a rough value for beginner users but it is well and truely open for discussion and I actually wouldn't apply it myself in the case of a Core2Quad. I guess the question then is, if not 20C, then what? Maybe 25C as you use?

Also, I personally wouldn't run a CPU closer than 20C to the 0C DTS point at 24/7 settings regardless of whether it was at 2.4Ghz or 3.4Ghz so I may have misunderstood what you're saying there.

Conclusion ? Software based for absolute CPU temp reading is NEVER ACCURATE, period !

That's my conclusion and it applies to all Core processors. There's a reason why Intel engineers outline such an elaborate process to come up with an accurate Tcase temperature.

Absolutely and that's fine for you, Bing, myself and everyone else who has followed this thread but I guess you're missing the point of my post . My point was that this information needs to be easily accessible to the average overclocker and it doesn't appear to be.

The new revision G0 processors, especially the dual cores, use significantly less watts at idle than the previous B2 processors ( 8W vs 22W ) when C1E is enabled. That's even less than the 12 watts that the L2 processors ( E4x00 ) are rated at. This is resulting in some impossible looking idle temps that are well below ambient when air cooled. For me, it's just more proof at how inaccurate the DTS is at reporting low idle temps which it was not designed for. I believe the DTS may start losing accuracy below 50C so even load temps for well cooled G0 dual core processors at default MHz and voltage may not be accurate.

This seems to contradict your previous statement agreeing that software based absolute temperature are inaccurate. If they're inaccurate for absolute temperatures, I can't understand how they can be used to indicate that the CPU temps are lower than ambient?
Admittedly my understanding of thermodynamics is reasonably limited but I find it hard to believe that any amount of current could exist at a lower temperature than the air that's being used to cool it (Note: I understand about surface area and heat transfer)


At the risk of repeating myself, I guess you're missing the point of my post. My point was that this information should be easily accessible to the average overclocker. From the large amount of threads on this subject here and at other online OC forums, it currently doesn't seem to be.
From following this thread I assumed that there was enough know-how and experience here to put something together that could be of great use to the wider OC community.