He's very big on Photoshop, so he wanted to have a lot of RAM to run it with. This is a graduation present for him-I got him the most RAM I could within the amount of money his parents allowed him to use.
The 6850 isnt going to be bottlenecked by an i7 960, even two of them in CF will be just fine. A few things i would change though.
Xtreme Gear PSUs are utter crap, get them to put something like the Corsair 650TX or a 650W unit from XFX in there if you want to CF down the line or a good 550W unit from Antec, Seasonic, or Corsair if you only plan on doing one 6850, a 700W unit from Xtreme Gear is rated for about the same amount of power as a decent 500W unit is and they charge you much more.