here's a shot at it. The only thing missing is a case which hopefully you have one lying around. if you need one then some tweaking will have to be done as there is room to go cheaper but this covers the rest for $600
PCPartPicker part list:
http://pcpartpicker.com/p/ZGYFHx
Price breakdown by merchant: http://pcpartpicker.com/p/ZGYFHx/by_merchant/
CPU: AMD FX-8320 3.5GHz 8-Core Processor ($124.99 @ Amazon)
Motherboard: Gigabyte GA-970A-DS3P ATX AM3+ Motherboard ($68.99 @ Directron)
Memory: A-Data XPG V1.0 8GB (2 x 4GB) DDR3-1600 Memory ($79.99 @ Newegg)
Storage: Western Digital Caviar Blue 1TB 3.5" 7200RPM Internal Hard Drive ($51.99 @ Directron)
Video Card: MSI Radeon R9 270X 2GB Video Card ($144.99 @ Newegg)
Power Supply: XFX TS 550W 80+ Bronze Certified ATX Power Supply ($53.98 @ Newegg)
Operating System: Microsoft Windows 8.1 (OEM) (64-bit) ($89.98 @ OutletPC)
Total: $602.91
Prices include shipping, taxes, and discounts when available
Generated by PCPartPicker 2014-11-18 19:08 EST-0500