Hello! I have Dell optiplex 760 Intel Core 2 Duo E8600 3.33Ghz., motherboard M858N, 6gb Ram, GeForce 550Ti, PSU Fractal design Tesla R2, 500W. My problem is my video card geforce 550Ti. Everything goes ok that time when i need to restart my cpu after install video card driver and monitor shows "going to sleep." I'll do everything possible: change bios setting integrated to my video card, latest drivers all around, test other cpu my video card and works fine, test other vid card my computer and works fine, truying other monitor, but some reason my own 550Ti dont work! WTF is wrong this cpu? Could be motherboard doesn't support my video card? Sorry my english not so good...