Computer restart with game launch

[:1]I recently bought SupCom2 from Steam, I had some problems installing, but once I got past them I figured that it was fine. I tried to launch the game and as soon as I hit play from the Steam menu my computer restarts. I tried again and it worked fine. It seems to happen about 50% of my attempts to launch the game. Any ideas for a fix?|||try reinstall the game full unistall and reinstall
and if that fails defrag your pc|||What a really strange error!|||I have kind of the same problem.
When i not directly start SC2 after boot, it always reboots my PC.
So when i start an random application and then SC2 it reboots. When i exit SC2 and start it again it reboots.
I even did a fresh install of windows XP SP2 without any updates and installed SC2. Still the same issue.
I am generally not a windows user. I only start windows to play SC2 so its not that big deal but its annoying.|||I upgraded to Service Pack 3. Problem solved