# [SOLVED] CPU Fan constantly changing speeds



## chasep (May 7, 2012)

Hello everyone, I noticed about a month ago that the CPU fan inside my eMachines ET-1641-02w started to pretty much spas out. What happens is lets say I want to open My Computer. Almost as soon as I move my mouse the speed of the fan goes up and up. There have not been any hardware/ software changes lately, and only goes at the normal fan speed when the computer is sitting on the desk, not in use. I read that it could be defective, but that was from Acer's website. Can anyone help, as I cannot afford a new fan?


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## makinu1der2 (Jan 1, 2008)

*Re: CPU Fan constantly changing speeds*

Have you checked the inside of the PC to see if it needs cleaning?

If not I would suggest doing so.


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## chasep (May 7, 2012)

Actually yes. The case is open right note because I had to move stuff from my moms old HDD. It is not dirty all


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## visseroth (Oct 25, 2010)

*Re: CPU Fan constantly changing speeds*

Check to make sure the heatsink is properly seated. If it wobbles around on top of the CPU then that would explain why your fan is is making so much noise as it is trying to cool off something that it's supposed to be pulling heat off of. Be sure you have the proper amount of heatsink compound between the heatsink and CPU.


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## chasep (May 7, 2012)

The heatsink is seated, it does not move. But what do you mean by that second thing to try


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## visseroth (Oct 25, 2010)

*Re: CPU Fan constantly changing speeds*

Well as long as the heatsink is seated properly and you have the proper amount of heatsink compound (IE Arctic Silver ceramic or Arctic Silver 5 which are my preferences) and your heatsink is clear of lint, dust and other debris then you may very well want to order up some heatsink compound and pull the heatsink. Clean both the CPU top and heatsink with Isopropyl alcohol (preferably 99% Isopropyl) and apply new heatsink compound. If that doesn't help then a CPU heatsink upgrade may be your best option.


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## Tyree (May 10, 2009)

*Re: CPU Fan constantly changing speeds*

The OEM heatsink fan should have no problems properly cooling the CPU if it's clean. How old is the PC?
Boot to the Bios, check the CPU temps and see if the fan RPM's fluctuate while in the bios.


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## chasep (May 7, 2012)

*Re: CPU Fan constantly changing speeds*

Ok but when it boots up the fan goes at a fast speed that would be normal if it was turning on but then it will stay at that speed


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## Tyree (May 10, 2009)

*Re: CPU Fan constantly changing speeds*



chasep said:


> Ok but when it boots up the fan goes at a fast speed that would be normal if it was turning on but then it will stay at that speed


Is that when you boot to the Bios?


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## chasep (May 7, 2012)

It turns on them speeds up, but normally should slow down. It usually slows down if I don't use it but if I log on rift away or move by mouse it will speed up right away


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## chasep (May 7, 2012)

Also the PC is at least 2-3 years as that is my best guess necessary it was secondhand from my moms friend


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## visseroth (Oct 25, 2010)

*Re: CPU Fan constantly changing speeds*

I would try re-seating the CPU. Sometimes the stock CPU compound doesn't get pushed out all the way and doesn't cause any problems for quite a while.
You'll need CPU heatsink compound which can be bought at most computer stores and online.
99% isopropyl alcohol
and a lint free cloth to clean both the CPU and heatsink.
You'll need to remove large chunks of CPU compound prior to cleaning with alcohol. Use something plastic that you don't mind getting dirty like a plastic putty knife to scrape away the old compound.
Clean the heatsink and CPU with the alcohol and let air dry
Apply a pea sized amount of CPU heatsink compound to the middle of the CPU and then set the CPU in place. give it a little bit of a wiggle around to get the compound to move around a bit and spread over the CPU and once the heatsink is tightened down and secure turn the machine on and check your temps again.


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