I worked on my friends computer yesterday. His CPU fan has being doing what I would describe as "pulsing". It speeds up in short bursts for about 2 seconds at a time, about every 2-3 minutes or so.
I opened up the case, cleaned out the fan blades, and oiled the fan bearing (with clipper oil). It is still doing the same thing.
I don't know what his system specs are, other that its an eMachines, with an AMD Processor.
The thermal paste could also stand to be removed and reapplied or better yet if you can get access to the back plate on the mobo and or remove the mobo (big job) you could look at a higher quality cpu cooler or even a 120mm sealed water cooler?
I don't think it would be cost effective to put a water cooled set up on a low end budget systems.
When was the last time anyone ever turned an eMachines system into a Gaming or CAD Rig?
I am going to re apply a fresh coat of CPU themal paste. I am out right now, I just ordered a new tube on newegg.com
Also look to the PSU and make sure you blast it clean with air, make and remake all the connections to the mobo and other powered components....never hurts. If it still happens then could be pointing to the PSU or mobo.
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