Explaining of Core 2 Duo temperatures

[Battleneter2]

There is a lot of confusion surrounding safe Core 2 Duo temperatures concerning Tcase and Tjuction.

Lets start with this, when someone states ""my CPU temperature is 70C"" is this safe or not? Well it depends on what readings they are looking at.

I have used 4 common programs to display temperature

TAT
Coretemp
Easy Tune (gigabyte boards only, Asus etc have there own software)
Speedfan

Tjunction max (in red) max temp threshold is (85C). It is logical to assume Tjunction is fine at to say 75C (as long as Tcase is below 61.4C). This issue becomes a little more complicated as the gap between Tcase and Tjunction can varie on different machines depending on the type and quality of cooling.

Tcase max (in Yellow) is (61.4C). Intel clearly show in the following PDF 60C is safe for sustained periods of time. At 60C (Tcase), Tjunction is usually substantially higher.

For a more detailed description please refer to the following Intel official Specification PDF.

http://download.intel.com/design/processor/datashts/31327802.pdf

Add to all of this Tcase seems to be read/calculated a little differently on certain software.

Basically when stating a temperature you should state the software used. Also when giving advice to others concerning temperatures, Tjunction or Tcase needs to be determined first, 70C can be fine or it can be terrible. It is better to know both Tcase and Tjunction temperatures.

 

[Battleneter2]

You may ask, why all this confusion concerning a fairly simple issue?.

The following picture says it all

http://s82.photobucket.com/albums/j254/Battleneter/?action=view&current=coretemp.gif

As you can clearly see, both "versions" of coretemp show the same temperature reading however one is described as "Tcase" and the other "Tjunction". The later vertion is correct "Tjunction".


I am uncertain if Intel released mis-information in the early days of Core 2 duo or the util writers simply got it wrong.



What ever reason for this mistake, in the early days of C2D many people felt they needed to cool there C2D way below what they actually needed too, and the stock cooler for example got a very bad rap when actualy it is not bad at all.



Any correction or things to add would be welcome (preferably with solid recent links). It would be nice to point to this thread to clear this issue up.

 

[Jalidi]

If you're speaking specifically about C2D's, they're designed to throttle at 85C. The Tjunction is the same value, and well, it's a fixed number which doesn't tell you anything about your temperatures.

Coretemp takes its temperature readings from a thermal diode inside the C2D. The other temperature monitoring programs take it from a thermal diode on the mobo or elsewhere. Thus temperature differences will occur between some comparisons of different applications.