the AMD combo you selected has been discontinued I like your choice of GPU, its a good buy. the PSU is also solid and with hold the a pair of 6850's in CF.
Here is a Sandy Bridge build that uses most of the parts that you picked out. it will out perform the AMD build for gaming. I used a MB that has CrossFire, because oyu selected yes to that question. if you drop the CF requirement you could save a little more money with less expensive MB and a ~500w PSU.