Company of Heroes
There's nothing much to separate the single-board X2 and twin-card Radeon HD 4870 setups, lending further credence to the 'doubling-up' methodology used by the HD 4870 X2. CrossFire provides up to an additional 72 per cent performance above a single HD 4870.
In terms of single-card numbers, ATI has the beating of NVIDIA's GeForce GTX 280 here; handily so at 2,560x1,600.