The Inquirer has posted a review of a Club 3D X850XT CrossFire master card.
We tested a master card as a single card as well just to show you the difference but I am sure that if you buy a master card you will want to buy a slave card and run them together. Crossfire is running some 50 percent faster in Doom 3 than on a single card. Our far cry test was CPU limited so even the two cards didn’t show any difference. Half Life was also limited and we could not see any difference till we turned anti aliasing on. Quake 4 was scoring some 12 FPS faster with two cards getting it to almost to 100 FPS. FEAR was an interesting one as it actually scored less with two cards than with one. If you buy those two cards we strongly recommend running in single card mode till ATI solve this driver issue.