|Then I started CS:S and my comp restarted... wow
I believe a any graphics and CPU intensive application will stress your system more than a CPU intensive application alone. Many laptops have a combined heatsink for the graphics and CPU. So when your graphics chip is putting out a lot of heat, you end up reducing the heat removal capabilities of your processor. This will cause the processor to have problems that wouldn't normally arise with a CPU intensive application alone.
For testing on a laptop we need to stress both the graphics system and processor to test stability. So CS:S seems good, but if someone doesn't have that available running Prime95 and something like the OpenGL Geometry Benchmark at the same time should also do the trick.
Does anyone know a better application, that will report errors like Prime95, and test the video with the CPU?