You should listen to your PC, say’s Propellerhead and he’s not talking about MP3 tracks but the noises it makes when you first boot up, and whilst it is running. Any change to the sound of your PC should ring alarm bells.
A low level whine that gradually disappears after a while is almost certainly the first sign of a CPU cooling fan failure. Get it seen to immediately, when it finally dies, and it will, the CPU can go into meltdown in less than a minute. At best it will automatically shut down and you’ll loose whatever you were working on; at worst the chip could fry and you’ll face a hefty repair bill.
A sudden increase or change in hard disc chatter, could be a sign of trouble to come, or more likely a badly fragmented drive, either way make sure your backups are in good order then at your earliest convenience run Defrag and the hard disc Error Checker (right-click the disc icon in Windows Explorer and select the Tools tab).
Noisy CD/DVD drives could also be a sign of wear, though a lot of the time it’s down to cheap and nasty discs, so try switching brands. If the noise persists replace the drive as it may well be on its last legs. For hundreds more tips tweaks and some of the best freeware programs around visit PCTopTips