Usually when teaming video cards linked in SLI or Xfire, they are same brand and card. Mixing cards you can run into issues. Id try to find 2 cards of the same make/model if doing this. Otherwise maybe you will get lucky and not have issues, but when a manufacture makes cards and tests them, they test them to be teamed with the same exact card, not another brand card. So there is risk you will run into troubles and both manufacturers say sorry charlie when they dont play well together and you contact support because your mixing cards/brands.
There is a slight clock offset between these cards and the faster card would have to downclock a little to sync to the slower clocked video card. If it works you will have much better performance than a single card and the slight downclock shouldnt make a difference, but you have a risk of bugs/glitches with a mismatched pair.
