What MOBO should I purchase for a 6950/6970 GPU?

I had a build all sorted out and then I cleared my bookmarks, losing all the parts I wanted lol. I remember most of them, but the build would have been $1475 (approx.). I want something a little cheaper, around $1,200 at max. I would also like to purchase a radeon 6950/6970 instead of the 6870 I wanted to purchase before. Any ideas on what mobo would be great for this gpu and have ample room for it. USB 2.0 and 3.0 would be nice too :). Thanks.