How about use the i3 + gtx960 for the $630.
PCPartPicker part list:
http://pcpartpicker.com/p/XyCbZL
Price breakdown by merchant: http://pcpartpicker.com/p/XyCbZL/by_merchant/
CPU: Intel Core i3-4150 3.5GHz Dual-Core Processor ($104.75 @ OutletPC)
Motherboard: Asus H81M-D PLUS Micro ATX LGA1150 Motherboard ($44.49 @ Newegg)
Memory: G.Skill Sniper 8GB (2 x 4GB) DDR3-1600 Memory ($59.99 @ Newegg)
Storage: Seagate Barracuda 1TB 3.5" 7200RPM Internal Hard Drive ($47.89 @ OutletPC)
Video Card: Gigabyte GeForce GTX 960 2GB Video Card ($190.11 @ SuperBiiz)
Case: Enermax ECA3253-BL ATX Mid Tower Case ($37.99 @ Directron)
Power Supply: EVGA 500W 80+ Bronze Certified ATX Power Supply ($37.99 @ NCIX US)
Optical Drive: Samsung SH-224DB/BEBE DVD/CD Writer ($14.98 @ OutletPC)
Operating System: Microsoft Windows 7 Home Premium SP1 (OEM) (64-bit) ($88.98 @ OutletPC)
Total: $627.17
Prices include shipping, taxes, and discounts when available
Generated by PCPartPicker 2015-02-26 16:59 EST-0500