I have Windows Professional--my computer shuts down and restarts quite often, I have taken it to two different computer shops and they cannot find the problem. Sometimes I receive a "Blue Screen" and it says "dumping physical memory", but usually the screen just goes black and the computer restarts itself...I have been dealing with this problem for months, Windows Professional was just re-downloaded on my computer, but I am still having problems, but only after my computer has been on for a few hours...the computer shop said they left my computer on for days and did not have any problems...but I don't know if they actually used the computer...Help!