I'd be much happier with this:
PCPartPicker part list:
http://pcpartpicker.com/p/KdC3Hx
Price breakdown by merchant: http://pcpartpicker.com/p/KdC3Hx/by_merchant/
Benchmarks: http://pcpartpicker.com/p/KdC3Hx/benchmarks/
CPU: Intel Core i3-4130 3.4GHz Dual-Core Processor ($119.97 @ OutletPC)
Motherboard: ASRock H97 PRO4 ATX LGA1150 Motherboard ($89.98 @ SuperBiiz)
Memory: G.Skill Ripjaws X Series 8GB (2 x 4GB) DDR3-1600 Memory ($72.00 @ Newegg)
Storage: Seagate Barracuda 1TB 3.5" 7200RPM Internal Hard Drive ($54.43 @ OutletPC)
Video Card: PNY GeForce GTX 770 2GB Video Card ($309.99 @ Amazon)
Case: Corsair 200R ATX Mid Tower Case ($39.99 @ NCIX US)
Power Supply: XFX 550W 80+ Bronze Certified ATX Power Supply ($26.99 @ Newegg)
Total: $713.35
(Prices include shipping, taxes, and discounts when available.)
(Generated by PCPartPicker 2014-06-01 14:23 EDT-0400)
The i3 will generally match an FX in most gaming benchmarks, slightly behind in some, slightly ahead in others (generally those that like stronger per-core performance).
I chose a H97 motherboard since it will have support for Broadwell when it releases. The AMD AM3+ option however has no upgrade path, and the AsRock 970 has no potential for overclocking. So essentially you're stuck with the performance you get, which isn't too impressive.
The i3 however will be able to be upgraded to an i5 or i7 later that will outperform even a heavily overclocked FX CPU.
The
main difference however, is the GPU. I chose a GTX 770 that will outperform the 280x in most circumstances. This will be the main factor affecting your gaming performance.
Also, you should take 2x4GB of RAM over 1x8GB. Dual channel operates better.