I built a P.C. for a friend of mine a few months ago. It's been running smoothly but a little warm. We decided to get him a Hyper 212 Evo. We installed the fan and everything went smoothly. Now we boot up his P.C. and everything powers up, all fans spin, no scary beeps, green light on mobo. but we don't get a display. Any Ideas? Help would be greatly appreciated. Thanks in advance folks.