My PC makes a buzzing sound, but stops when i tap it.

[TheDankestWaffle]

So I bought this pc from a buddy and when i got it it was pretty dusty. I ignorantly barely cleaned it and have been running it for about two weeks. Last night it started making a buzzing sound so i tried to move the pc to see about taking the side panel off and the second i moved it a little bit the sound stopped. This happened for quite a while until i started to tap it. At the place where I tap it, (top right of the motherboard, above the hard drive bay), i also tried applying pressure to it and once i put enough pressure down the sound also stops. i have to press hard though. I took off the side panel and checked to see what was wrong but nothing is where i am pushing down? I also cleaned the PC very well in hopes to quiet the fans and stop the noise. The noise did stop for quite a while and the fans got very quiet but recently started getting louder and now the sound is back. I will try to get a soundclip up soon to see if that helps. Thanks.

 

[R4DIO4CT1VE]

Its either a fan or a harddrive. I would bet on it being a case fan.

if you can't listen and figure out which fan is making noise, go through and check each fan by unplugging it (fan headers are labeled on motherboard just make sure you dont unplug CPU FAN). If you unplug a fan, and the noise no longer appears, well you know which fan is the problem.

if you find the fan making noise, buy a new fan.