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I think the question is self explanatory:

I have a server (running Linux) which has 2 CPUs with 2 cores each. I know how to turn off cores and fans pragmatically. If for example, I turn off both cores in CPU#2, I guess its fan is no longer required. It would be reasonable to turn it off as well?


Temperature of last week. Core0 (orange) & Core1 (yellow) of Cpu#2 were turned off 3 days ago. Core1(blue) of Cpu#1 was turned off 1 day ago. Still, the temperatures doesn't change: enter image description here

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Other circuitry in the chip will be active, but it shouldn't generate much heat compared to the cores. It should be safe to turn off the fan once the chip temperature has reached a reasonably low value.

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One can use e.g. the fancontrol package to set PWM values on fans depending on reported temperature, including turning fans off if the temperature falls below a defined value. – Daniel Andersson May 10 '12 at 7:40
@Ignacio: Thanks for the answer... I just have a question: how do you know that? (sorry, I just want to be 100% sure about it). – lepe May 11 '12 at 0:42
@Daniel: Yes, I thought about it too, but it seems the temperature hasn't change so much even with all cores turned off (probably because it is not hot season yet). I added the temperature chart to show it to you. In that case, how do I know it reaches a "safe" temperature? – lepe May 11 '12 at 0:46

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