post #11 of 11
First thing is that your Case temp of 64C is wrong. The CPU die or case temp (TCase) cannot be higher than the 2 core temps (TJunction). It must and will be 7-12C cooler.

The Core 2 Duo chips have an on board digital temp sensor for each core which returns a temp x many degrees from the Junction point - the temp where chip is throttled back to avoid damage. The bios attempts to make an educated guess as to what the TCase temp is based on the core temps. Many times the bios is wrong.

For example, the TJunction on your e6600 is probably 85C. If you measure the digital sensor data you might get something like 55C at idle which means that the core is 85-55 = 30C. You can measure this sensor data directly using a tool called Crystal CPUID. Here's what to do;

A) Use a program called coretemp and find your tjunction - it should be 85C. You can also read your core temps as well.
B) Download crystal cpuid; http://tinyurl.com/24k6su
C) In CPUID, run Function/MSR Editor and enter 0x19c in the MSR number box - this is the register for the DTS sensor.
D) click the RDMSR button - In my case I get a value under EAX of 0x88370000.
E) Take the last 2 numbers before the 0's (37) and enter this Hex number into the Windows scientific calculator. Click the hex option, enter 37, and click the Dec option. You get 55. You subtract this value from the TJunction point, 85C and get a true core reading of 30C.

Once you have this accurate core temp, you can offset speedfan so that it shows a more realistic Case temp. Simply enter -15C as an offset to the 64C temp and that should fall inline with the core under load.

You will find that Coretemp is very accurate and gives the same reading +/- 1.

This TJunction or Coretemp is what you should be concerned about when overclocking. It is the temperature in the CPU that the Thermal Management and Throttling is based on. Generally you do not want this temp to be higher than 50-55C running Orthos under load.