Thread: TIM
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Old November 18th 07, 09:24 PM posted to alt.comp.hardware.overclocking.amd
Paul
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Default TIM

Robin wrote:
Which brand do you recommend. My arctic cooler64 Pro used to cool my OPty
144 without a hitch but it's lost trying to cool an FX55 would a different
TIM help the cooler work more efficiently.

TIA

Robin



An FX-55 is 104W TDP, while an Opteron 144 S939 is 67W.
That means the cooler has more to do, and things will get hotter.

The TIM only adds a bit to the thermal resistance of the assembly.
A good cooler would have a theta of 0.20C/W or so, while the
TIM only adds a fraction more to that. Therefore, when you want
a better cooler, find a cooler with a lower theta value. Very few
manufacturers quote theta (Zalman does, but not for all
products - one other manufacturer gives a linear curve, and the
slope of the line is theta).

You can work out the expected temperature.

CPU_temp = case_internal_air_temp + theta * power_dissipated_in_watts.

Test the Opteron 144 by running Prime95 or any good CPU loading program.
Record the temperature of the computer case air, and the CPU temp.
Solve the equation and get the theta value. Assume the loading program
causes the processor to draw "TDP" watts.

Then, re-evaluate the equation, substituting 104W in place of the
67W. The new computed CPU temperature should bear some resemblance
to your measured results for the FX-55.

Paul