If it's not going to be OC'ed, then the water cooling kit can go and he can buy an SSD. AData, Kingston or OCZ are brands I recommend.
Edit; also, if it's strictly gaming, then you should go dual-core instead of 6-core. No games suport 6 cores. Hell, not all of them support dual-cores yet.
ummmm.... in case you haven't noticed, AMD doesn't HAVE a dual-core FX. 6300 is a good gaming cpu, frequently reccomended here. I agree, get an ssd over a water cooler
I agree, buying a cooler in that price range basically blows away the logic behind choosing the FX over an i5.
I'd have to disagree on the dual-core. We're experiencing a shift where most games will start needing more than two cores.
If it were an i3, it could be decent, but I believe you suggested the dual-cores to save some money, but the i3 line's price range is in line with the new FX CPUs, so the only reason I could see a person would want an i3 instead is if that person just wants a everyday PC, or when someone needs good single-threaded performance. An FX might deliver a little less FPS, but its other advantages more than makes up for that.
If you were planning something like a Pentium or Phenom II or Athlon II dual-core, they would most likely bottleneck the card.
Nah, get at least a quad core. There are some games out there that use more than two cores. I'm pretty sure BF3 will use as many cores as your cpu has.