H.A.W.X
H.A.W.X provides a DX10.1 path for newer GPUs, speeding up antialiasing. Now a year old, it's a good test of general GPU efficiency and, as a flight simulator, of multi-monitor setups.
Benchmarks
H.A.W.X confirms what we already know. Sapphire's design is a notable step up from a reference HD 5970, but a true HD 5870 CrossFire configuration offers better results for less of your money.