Battlefield 2

The fastest SLI and CrossFire systems bunch up at the top of the field here, likely due to a frame rate cap of 90Hz built into BF2. Any of these setups can run BF2 about as optimally as it can be run at 1600x1200 with 4X antialiasing. The Radeon X1800 XL CrossFire system is in league with the GeForce 6800 GS SLI setup—based on a much cheaper class of card.

Guild Wars

We found the same thing with the Radeon X1800 CrossFire systems that we did with Radeon X850 XT CrossFire. The game apparently has no profile in ATI's drivers and defaults to SuperTiling mode, which actually produces lower frame rates than one would get from a single card. You'll want to disable CrossFire altogether when playing games that trigger this sort of behavior.