An 850W PSU for a computer that has no graphics card nor any other similarly power-consuming configuration? That's a bad idea. You shouldn't go above a 430W or so on that system unless you intend to add some very power-consuming components soon. A way overkill PSU is almost as bad as an insufficient PSU.
That motherboard is almost three times more expensive than seems necessary for your system and about two times more expensive than the max that I'd recommend.
Also, what is it going to be used for? If it's for gaming, your CPU is way too powerful and you don't have a graphics card. If it's for computing, you're fine, aside from the ram. If it's just for general use? Then it's way off balance.
[Edit: My bad. Didn't see that you had 'custom' stuff below. Everything below this line is from the edit.]
Your case is too expensive, in my opinion. It's a good case, but for watercooling. I'd go with a phantom or a gamma classic if you're a fan of the brand. [Gamma classic is a $40 case that, aside from the front panel, performs like a $120 case without the fans.]
Your CPU is way overkill - gaming doesn't require hyperthreaded cores. Go with an i5-3570K if you're overclocking, or the fastest non-K model if you aren't. [Though with an aftermarket cooler, it looks like you are.]
Your motherboard is very nice, but again, could be way cheaper. Check out the Tom's article on value gaming MoBos: http://goo.gl/89grt
I'm blown away by the fact that you found a 670 for $340 - that makes a value card even more worth it. Your CPU is a bit overkill, though. The AX650 can pull 900W if needed, which would be enough to power a rig with two 680s. I would go with either that model or the HX750. It's an extremely good part that got upgraded to be 80+ Gold certified. [Just make sure you select the 80+ gold version.]
ok, this is for editing and gaming, there will eventually be 2 gpu's, and i chose that gpu becaue the 650w was only $10 cheaper and the 750w was $1 more lol. and im going to watercool, thats why the case, also i just like it, i think its worth the little extra $