I have just built two almost equal builds. First build is working fine. I the following parts: Asus Sabertooth z77 Intel 3770K CPU Corsair 16gb 2133mhz memory sticks The first computer went up straight away not issues. The second computer wont display anything. Have tried with onboard gfx and ATI 7970 gfx card. Also tested with an old 5970 gfx card still no image. Other then the gfx card, there is also a diffrent PSU. The first computer got a 1000W, and the seconds has a 750W PSU. So what can it be? Shouldent 750W be enough to drive the equipment? Or mabye the MOBO is DOA? Hope someone has any suggestion?