This suggestion would change your build around, but have you considered getting an Intel processor over AMD? Getting the Intel i5-3570k would be a bit more expensive, but the performance boost and "future-proofing" it would provide could be worth it.
Either way you don't have to worry about bottlenecking your GPU, so it's certainly not critical; it would just give you some breathing room if you ever decided to upgrade your GPU. Looks solid! (Supahos is absolutely right about the motherboard though)