Two years ago a friend of mine purchased my old PC and recently it started freezing on him while playing Starcraft 2.  I wanted to stress test the rig to make sure it wasn’t a hardware issue so I ran the standard CPU tests of calculating Merseinne primes,  the first trillion digits of pi, and solving rainbow tables but I needed something to test the video card.  After poking around, the industry standard appears to be seeing how quickly your computer can render frames of a spinning torus covered in fake fur being blown by a fan.

CPU testing – Find an odd perfect number.

GPU testing – Imagine a wind-buffeted squirrel bagel.