Best GPU for my build?

PrankDudeTb

Honorable
Jan 23, 2014
58
0
10,640
heres my parts so far

1TB Western Digital Caviar Blue Hard Drive
4GB Corsair Vengeance DDR3 RAM x2
AMD APU A8 6600K
Corsair Builder Series CX430 Watt Power Supply Unit
Gigabyte F2A85XM-D3H Motherboard
Corsair Carbide Series 300R-Tower Gaming Case
XFX Radeon 7770 GHz Edition
Lite On DVD Burner

so what could i put in for a better gpu FOR THE SAME PRICE RANGE