I recently just purchased: Gigabyte P55A-UD3 Motherboard Intel Core i5-650 Clarkdale 3.2GHz Corsair XMS3 4GB (2 x 2GB) 240-Pin DDR3 Using my old: Nvidia 8600GT 550W PSU. When I start up my computer I get one short beep, in the manual says normal start up noise. But I get no video output from my computer. Have tried different cables, and monitor. Recently purchased a new Geforce 9400 GT thinking my video card was shot. But still no video output. Thank you for your help.