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Question

CPU runs hard at times

Mar 16, 2015 1:17PM PDT

Sometime my cpu fan just runs so hard for like 3-5 sec and then stops happens maybe 5 times a day? Is there something I can download to scan or something? I just want to make sure that it won't mess up my computer

Discussion is locked

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Answer
Is this a laptop?
Mar 16, 2015 2:18PM PDT

That's normal for when it gets hot. Desktops can do it too. It usually is the CPU fan you hear doing that. It can indicate need for new temperature paste under the heatsink if the computer has had hard use or a couple years old.

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Its not a laptop
Mar 16, 2015 2:35PM PDT

this computer is around 2-3 years old would that mean it would need that paste??

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Probably
Mar 16, 2015 2:40PM PDT

It's the most likely cause. Not to expensive, about $5 cost, and not too difficult, but DON'T take out the processor when doing it. The new ones are so sensitive it's easy to bend a pin on the CPU or the socket, depending on maker. Removing the HSF, putting the right size glop of paste, and then resetting the HSF and locking it back down isn't that difficult.

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Cpu fan
Mar 16, 2015 2:47PM PDT

Its the cpu fan that just speeds up I read something about that it could possibly be a virus? The cpu fan runs fast like speeds up for like 5-7 seconds then stops?

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Picture
Mar 16, 2015 2:48PM PDT
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That's boiling hot!
Mar 16, 2015 3:00PM PDT

It's 110-120 Centigrade which is well past boiling water at 212 Fahrenheit. It should stay below 70 C aka 160 F.

Touch the top of your desktop and see if it's almost too hot to hold your hand on?

Check the fans at the back and be sure they are all still blowing outward.

Take the side off and watch the CPU fan, be sure it's running constantly. It might be stopping and then coming back on and trying to catch up to the heat. If so, needs replacing NOW.

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It could be in error
Mar 16, 2015 3:24PM PDT

but considering the fan cutting on faster, maybe not much. Here's an screen capture someone did for the same basic CPU showing how they got two different temperature readings, while letting it sit at idle.

http://postimg.org/image/l37oin0i7/

What I do, since I use Linux, is use the program that allows calibration. I let mine go to sleep and the next morning soon as it comes back up, I check the temps shown. I know the hdd temp should be near room temperature (I have a digital wall thermometer) and I know the CPU should be no more than 10-20 degrees hotter just from waking up after all night sleep. I set those in the temp measuring software. Another think one can do is put a thermometer near the top fan, blowing from the PSU on most desktops, see if it's getting more than 20-30 F above room temperature.

If your very high heat readings are correct, you could measure the inside of case using a meat thermometer from the kitchen!

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I guess he fried it
Mar 24, 2015 1:01AM PDT

no comeback. Lay it on side, put a grill on top, turn into a fancy hibachi. Wink