Can you make me a budget for a mid-range gaming desktop computer?

PCPartPicker part list / Price breakdown by merchant / Benchmarks

CPU: AMD FX-6350 3.9GHz 6-Core Processor ($134.99 @ SuperBiiz)
CPU Cooler: Cooler Master Hyper 212 EVO 82.9 CFM Sleeve Bearing CPU Cooler ($29.98 @ OutletPC)
Motherboard: MSI 970A-G43 ATX AM3+ Motherboard ($39.99 @ Newegg)
Memory: Crucial Ballistix Sport XT 8GB (2 x 4GB) DDR3-1600 Memory ($64.99 @ Newegg)
Storage: Seagate Barracuda 1TB 3.5" 7200RPM Internal Hard Drive ($59.94 @ Amazon)
Video Card: MSI Radeon HD 7850 2GB Video Card ($109.99 @ Newegg)
Case: Thermaltake VL80001W2Z ATX Mid Tower Case ($24.99 @ Microcenter)
Power Supply: Corsair CX 500W 80+ Bronze Certified Semi-Modular ATX Power Supply ($49.99 @ Microcenter)
Optical Drive: Asus DRW-24B1ST/BLK/B/AS DVD/CD Writer ($16.99 @ Newegg)
Operating System: Microsoft Windows 7 Home Premium SP1 (OEM) (64-bit) ($89.00 @ Amazon)
Total: $620.85
(Prices include shipping, taxes, and discounts when available.)
(Generated by PCPartPicker 2013-11-19 10:58 EST-0500)

It'll be cheaper if you had a OS (64 bit)