I just tried to overclock my sparkle 8600gt only about 60 extra mhz and 60 extra memory and the screen went black and i had to reboot. Now when i go to the overclock settings on ntune both are set to 0 and i can't change them. I tried never winter nights and it still works the same but what could this possibly mean? the only thing i could think of is that the card died by overclocking it this small amount : /