Loud noises coming from power supply fan?

it might be the fan of your cpu has dust.and making it the fan hard to spindle.if you can dismantle your cpu fan or the fan in your power supply.just clean it with the paint brush.or do it with vaccum cleaner.if you have air compressor the would be better.just blow out the dust.then if you can do it also just putting oil or grease inside the fan at the core.the one that has magnet.it will smoothen the spindling.ok good luck