Lesson Learned...Clean Your Laptop
I've been having trouble with my laptop shutting down unexpectedly. After some searching online, I found out that this is a common problem with my laptop (HP ZD8000) that the fins that cool down my desktop CPU get dirty. So I got a can of air and screwdriver and went to work. OMFG!
Here's what was lurking in my laptop:
Lesson learned, clean your laptop (especially if it is a desktop-replacement). Since I have a desktop hyperthreaded CPU plus a X600 with 256 Megs of Video memory. When I run World of Warcraft, this bad boy heats my house in the winter. Dirt == hot == shutdown.