PCPartPicker part list:
http://pcpartpicker.com/p/ZsLpP6
Price breakdown by merchant: http://pcpartpicker.com/p/ZsLpP6/by_merchant/
CPU: Intel Core i5-4570 3.2GHz Quad-Core Processor ($199.88 @ OutletPC)
Motherboard: Asus H81M-PLUS Micro ATX LGA1150 Motherboard ($69.99 @ SuperBiiz)
Memory: Kingston HyperX Fury Black 8GB (2 x 4GB) DDR3-1600 Memory ($42.99 @ SuperBiiz)
Storage: Seagate Barracuda 1TB 3.5" 7200RPM Internal Hard Drive ($46.87 @ OutletPC)
Video Card: Asus Radeon R9 270X 2GB DirectCU II Video Card ($154.99 @ SuperBiiz)
Case: Silverstone PS08B (Black) MicroATX Mid Tower Case ($35.99 @ SuperBiiz)
Power Supply: XFX TS 550W 80+ Gold Certified ATX Power Supply ($44.99 @ NCIX US)
Total: $595.70
Prices include shipping, taxes, and discounts when available