Mobo died so I upgraded a computer with... Mobo- ASUS M4A88T-V EVO AM3 AMD 880G HDMI ATX, Ram- G.SKILL Ripjaws Series 16GB 240-Pin DDR3 1066, CPU- AMD Athlon II X4 640 Propus 3.0GHz Socket AM3 95W Quad-Core. The GPU is GTX 550ti. PSU has 750 watts. I cannot get any signal from any montior plugged into this gpu. Also, I tried switching PSI-e slots with no change. What am I forgetting? Does the fact that this new mobo has onboard video interfere with the gpu?