PCPartPicker part list:
http://pcpartpicker.com/p/3ja1y
Price breakdown by merchant: http://pcpartpicker.com/p/3ja1y/by_merchant/
Benchmarks: http://pcpartpicker.com/p/3ja1y/benchmarks/
CPU: AMD Athlon X4 750K 3.4GHz Quad-Core Processor ($79.98 @ OutletPC)
Motherboard: ASRock FM2A55M-VG3+ Micro ATX FM2+ Motherboard ($42.99 @ Newegg)
Memory: Patriot Viper 3 4GB (1 x 4GB) DDR3-1600 Memory ($26.90 @ Newegg)
Storage: Hitachi Travelstar Z7K500 500GB 2.5" 7200RPM Internal Hard Drive ($49.99 @ Amazon)
Video Card: EVGA GeForce GTX 750 1GB Video Card ($125.38 @ Newegg)
Case: NZXT Gamma Classic (Black) ATX Mid Tower Case ($44.99 @ Newegg)
Power Supply: Corsair Builder 430W 80+ Bronze Certified ATX Power Supply ($19.99 @ Newegg)
Optical Drive: Lite-On iHAS124-04 DVD/CD Writer ($14.99 @ Newegg)
Operating System: Microsoft Windows 8.1 (OEM) (64-bit) ($89.98 @ OutletPC)
Total: $495.19
(Prices include shipping, taxes, and discounts when available.)
(Generated by PCPartPicker 2014-03-30 15:21 EDT-0400)