Windows 7: Frequent shutdowns during gameplay. Reason 0x500ff

In the last few months, my laptop has gotten worse and worse about random shutdowns, almost always occurring when playing a game, especially with higher graphic settings.
The CPU temps have been normal, they idle between 50-55, the GPU has been idling at about 73, which seems way too high, but I don't know if GPUs are supposed to idle as low as CPU cores.

I'm running on -
Sager NP8760
Windows Home Premium 64bit
ATI Mobility Radeon HD 5800 Series
Intel Core i7 Quad 720 @ 1.6GHZ

In the attached dump file, the reason code that keeps showing for the shutdowns is 0x500ff, but it says no title for this reason could be found.



Any insights would be greatly appreciated

That is very high temp for ideo GPU. Your GPU does not have sufficient cooling causing by deterioration of thermal paste. If you can, try to open the laptop where the video card located. Clean the old thermal paste on the chipset with alcohol and apply new thermal paste.