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I've seen that whenever I plug in an USB device like an external drive or bluetooth, immediately there is a rise in the CPU Temperature by 4-5 degrees celcius.

Do you know why this might happen?

I'm using Speedfan, Coretemp, and Easytune (the motherboards official utility) to measure the temperature.


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up vote 5 down vote accepted

The CPU goes from idle to performing an operation such as searching for the driver, starting the device, etc etc. Most CPUs are in a low power state when idle and interrupting then cancels this. I'm assuming that this 4-5 degree increase is only from idle. If you're in the middle of something CPU intensive, I get the feeling you won't see much temperature change.

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+1 Good answer. – hanleyp Oct 26 '09 at 12:15

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