I ran across a window that (to me) look like an over-clocking slide for my graphics card so I increased by one notch. Ever since then I have had the problem of my PC just rebooting when it feels like it, it seems to me. I have never been able to find that same window again. My Graphics card is a NVIDIA GeForce4 MX 4000, bios version 4.18.20.42.61. HELLLLP!!