Quake Wars: Enemy Territory
Performance is more even in Enemy Territory: Quake Wars, run at maximum detail. We see that memory-bandwidth is more telling than core and shader speeds in this instance, with the two-card HD 3870 CrossFire leaping ahead.
We can also see that CrossFire scaling is 'only' around 1.5x a single card's - one of the pitfalls on relying on a two-GPU approach, we suppose.