For games, GPU is more important, I change some of the components, RAM 1600mhz, HD7850, and the PSU. Even the price for three is $3 more, but the GPU is two-tier higher than r7-260x.
Also the MB is ok, and make sure use the better cooler with a top-down blowing design to cool down CPU and its surrounding components, if you have problem like the PC freeze during the games.
My list. PCPartPicker part list:
http://au.pcpartpicker.com/p/2sbLC
Price breakdown by merchant: http://au.pcpartpicker.com/p/2sbLC/by_merchant/
Benchmarks: http://au.pcpartpicker.com/p/2sbLC/benchmarks/
Memory: G.Skill Ripjaws X Series 8GB (2 x 4GB) DDR3-1600 Memory ($99.00 @ Mwave Australia)
Video Card: HIS Radeon HD 7850 2GB Video Card ($199.00 @ Mwave Australia)
Power Supply: Antec High Current Gamer 520W 80+ Bronze Certified ATX Power Supply ($85.00 @ CPL Online)
Total: $383.00
(Prices include shipping, taxes, and discounts when available.)
(Generated by PCPartPicker 2013-12-30 05:37 EST+1100)