I have a system with an HIS reference 5770. The problem is with even a slight bump anywhere in the case my monitor looses display and I can hear the graphics card fan ramping up and down. When I loose display though, I can hear that the system is still "on" but i'm not sure what state it is in because there is no display. I have checked temps and screws and the card is not overheating nor is it loose (as far as I can fell anyway.) Please help!