My wife uses This pc.
..Anyway recently the cpu fan has been speeding up intermittently. I know that supposedly this is normal operation, as in when the cpu gets a little too hot it speeds up to cool it down. However the only thing she does is play facebook games so it's a bit strange.
So I opened it up and cleaned blew out all the dust. Took off the heat sink, cleaned it and re-applied TIM. It seems to be running much better now. However there is no way to check the cpu fan speed in the cmos set up. There used to be until I updated the bios several years ago when I first got the pc as a hand me down.
I don't know but I wouldn't think the pc would get so hot even with a bit of dust, just playing facebook games....