if you're getting a loud noise, it could be due to your power supply going bust, in which case, your fan will go and then if you don't either replace your fans, power supplies, etc.., your mother board will be fried. best suggestion would be to backup your files and get yourself a new power supply. or else it could simply be your hardware vibrating too much (loose maybe?). also, it could depend on how old your computer is and how often you leave it on....which would help determine whether or not you need to replace some fans or the whole power supply.
Hope this helps.
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RiceBoy
Rice Boyz Society
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