My computer makes weird sounds

i need help, my computer does a big high sound than comes back to normal like a care when it drives it does this sound and when it stops the sound goes away... please tell mee. Does my computer need to be shut down.Does it need to be sleeping etc btw its a pc not laptop or mac

If the sound is not coming from the speakers, the problem is either from a bearing in a fan motor or the hard drive, CD player or floppy drive. In case it is the hard drive, the first thing to do is make copies of any important files on a CD or flash drive.

Remove the cover, locate the source of the sound and replace the defective component. If you don't feel comfortable doing that, enlist the help of someone who does or take it to a repair shop.