I would suggest the 8350 over the i5 because the 8350 is good enough for any current game and has the extra advantage of the extra cores when it comes to newer games. Hence this is what I would suggest :
+ AMD FX 8350, 8 Piledriver Cores @ 4.0 Ghz
+ AMD R9-280x GPU, just what you demanded for. Awesome GPU.
+ 8GB RAM @ 1866Mhz, awesome for gaming.
+ 1TB HDD, enough for storing just about any games, media, etc
+ Bitfenix Shinobi, awesome case with Neat cable management.
+ Seasonic 620W S12 II PSU, best quality PSU, also semi modular, would help with the cable management.