one of the cooling fan thingies keeps making a really loud abnormal whirring noise. and i have no idea why it starts... or why its stops.
or how to prevent it...
Not even kicking it helps!!!
Open up your case, BUT DON'T TOUCH ANYTHING (that means anything inside the case including fans, etc) and see if you can pinpoint which fan is making the noise. Most likely there is a wire or something else in its way. Turn off your computer and move the wire out of the way then. If there is nothing interfering with the fan, it may be time for a new fan.
Indeed. Dusted fans make a screetching noice. Sucks. You, from my experience, are better of buying a new fan.
If you are going to touch inside your PC (blahblahblah), make sure you've touched a raditator or something to get rid of your static electricity. You could seriously **** it up if you don't.