so it only started happening about a week ago and every time i turn on my computer at this point it does it. i know its from my psu because when it does it i can actually feel the vibration of my psu and its like a phone on a constant vibrate. it sounds like a lawn mower. its louder than you might think. im not sure if its the fan cuz im not sure how a fan could get THAT loud. but to get it to stop i have to punch it over and over and quite frankly, my knuckles are getting sore lol.