So I have a Gigabyte Radeon HD 7850 OC 2GB and I just picked up an Asus HD 7850 2GB. Tossed the new Asus in and added crossfire, enabled in Catalyst Control Center.
I've noticed a little improvement, skin in Mass Effect 3 for instance looks slightly better, other games I don't notice anything at all (Ravaged comes to mind.. the weapons take a few seconds to fill in the weapon detail after changing what you're holding).
Obviously this is not a top shelf gaming card, but it does pretty good. I'd like to see if there's a way to pull more performance out of these in Crossfire. Any tweak ideas?