I have Windows 7 Pro installed on my MBP and its started shutting down randomly and without warning. I havn't done a lot of testing so far, but heres what i've noticed. It started happening after I installed an OptiBay (http://www.mcetech.com/optibay/) and it mainly happens when i'm using battery power. The Win 7 is installed on the default harddrive, not the OptiBay. The latest time I was playing Age of Empires 2 and all of a sudden the computer just shuts down like I had held down the power button. And another time I was installing updates, but I was on a plug. It corrupted the partition and i had to restore it. My battery capacity is only about half of what it used to be, but I didn't run out of battery. Could it be a heat issue since i'm playing games? Or is it related to the OptiBay and the lack of an optical drive now?