We used the full retail version of Company of Heroes patched to version 1.7. All in game settings were set to their maximum expect for anti-aliasing and anisotropic filtering which were varied throughout our testing.
The game is set outdoors so there is heavy use of transparent textures for representing foliage and fencing. Therefore turning on transparency anti-aliasing has a big impact on performance. However, on this occasion we didn't test with this technique turned on.