I am currently using a 480 Watt PSU, but it my comps keeps going black screen on me, and i can't restart it. I still see lights on my tower, and hear my tower running, but when i press the restart button, i get no response. I would have ot manually shut down and turn it on again. Now my comp can not turn on for more than 5-10 minutse without going blank screen again....would this be a problem with my PSU?? If so, what PSU should i get?