PCPartPicker part list:
http://pcpartpicker.com/p/2tO5t
Price breakdown by merchant: http://pcpartpicker.com/p/2tO5t/by_merchant/
Benchmarks: http://pcpartpicker.com/p/2tO5t/benchmarks/
CPU: AMD Athlon II X4 740 3.2GHz Quad-Core Processor ($74.99 @ Newegg)
Motherboard: MSI FM2-A75IA-E53 Mini ITX FM2 Motherboard ($74.99 @ Microcenter)
Memory: Crucial 4GB (1 x 4GB) DDR3-1600 Memory ($38.84 @ Amazon)
Storage: Seagate Barracuda 500GB 3.5" 7200RPM Internal Hard Drive ($47.00 @ Amazon)
Video Card: Sapphire Radeon HD 7770 GHz Edition 1GB Video Card ($94.99 @ Newegg)
Case: Zalman ZM-T1 MicroATX Mini Tower Case ($24.99 @ NCIX US)
Power Supply: Corsair Builder 430W 80+ Bronze Certified ATX Power Supply ($19.99 @ Microcenter)
Optical Drive: LG GH24NSB0 DVD/CD Writer ($15.99 @ Microcenter)
Total: $391.78
(Prices include shipping, taxes, and discounts when available.)
(Generated by PtCPartPicker 2014-01-01 13:20 EST-0500)