Mine is an Intel machine and SP3 hasnt been installed. Pretty sure its related to automated update cause after stopping the service and setting it on manual start up things have been peachy. I've read more people who had this problem, best guess is the asociated executable is corrupted. I'll just copy all my file to the server (hardly any, most are on the server anyway) and do a clean install to solve this. Worst thing is I have to reinstall my games, prolly that will be most time consuming part..

This happened to my wife's laptop. I'm pretty sure it was a corrupted file but can't remember the name of it. We didn't reformat as the problem seemed to self-correct after about 2-3 weeks. However, reformating is probably best.