Here you go. Better motherboard, power supply, case, and video card.
PCPartPicker part list:
http://pcpartpicker.com/p/34l96
Price breakdown by merchant: http://pcpartpicker.com/p/34l96/by_merchant/
Benchmarks: http://pcpartpicker.com/p/34l96/benchmarks/
CPU: AMD FX-6300 3.5GHz 6-Core Processor ($113.48 @ OutletPC)
Motherboard: MSI 970A-G46 ATX AM3+ Motherboard ($69.99 @ Microcenter)
Memory: Patriot Viper 3 4GB (1 x 4GB) DDR3-1600 Memory ($30.99 @ Newegg)
Storage: Hitachi Ultrastar 1TB 3.5" 7200RPM Internal Hard Drive ($52.00 @ Amazon)
Video Card: MSI GeForce GTX 650 Ti Boost 1GB Video Card ($160.98 @ SuperBiiz)
Wireless Network Adapter: TP-Link TL-WN722N 802.11b/g/n USB 2.0 Wi-Fi Adapter ($11.99 @ Staples)
Case: NZXT Source 210 (Black) ATX Mid Tower Case ($29.99 @ Newegg)
Power Supply: Corsair Builder 500W 80+ Bronze Certified ATX Power Supply ($29.99 @ Newegg)
Total: $499.41
(Prices include shipping, taxes, and discounts when available.)
(Generated by PCPartPicker 2014-03-04 22:37 EST-0500)