I've had my computer for a couple of months, and it's been great so far. However, the other day I removed the DVD drive because it was getting jammed. It might not be because of that, but now the PC keeps turning off after a few seconds of the loaded desktop. It boots fine, loads fine, the desktop comes up perfectly, but after a few seconds the mouse lags and then the computer reboots with no errors or anything. What could it be? It runs fine in safe mode.