Although I realise these specs are modest, I did not expect an average of 14FPS from the performance test.
The benchmark tool in COH2 is old and broken. Ignore it.
Turn on the fps display in Steam and play a 1v1 match for your actual fps. You should start with well over 60fps. If it's still bad, let us know.
Steam -> Settings -> In-Game-> In-game FPS counter
Or you can use FRAPS for averages and stuff. It will go down as the match progresses though. No hardware can overcome the poorly coded engine.