OK so heres the deal i took my dads old computer. It was working just fine at the time. So i took it because he was upgrading computers. So anyways i set up his new comp. PC building intrigues me for some reason so i got into when he was upgrading. Anyways the computer that was working was disconnected so we could move hard drives and set up the new comp. So the dead one was down for a day. So we finished the new one and i took the old one put in a brand new 6790 ati gpu. But now it shows no signal on the monitor. Im about to switch to an older gpu, then an older cpu to see but what else could i do