What do you think of my build?

Solution
The motherboard uses a 2 generation old 760G chipset that was never designed to run an FX processor . It can , but its not ideal .
Instead pay a little extra and use a board with a 970 series chipset .

The asrock 970 extreme3
http://pcpartpicker.com/part/asrock-motherboard-970extreme3r20
or
Asus M5A97 R2.0
http://pcpartpicker.com/part/asus-motherboard-m5a97r20

The cm power supply is not suitable for use with a modern computer .
Use only 80+ bronze or better rated power supplies .
The Corsair CX 600 is $45
Now a days you really need 8GB of RAM. So it is a little more costy, but in the long term the 8gb Ram will help.
PCPartPicker part list / Price breakdown by merchant / Benchmarks

CPU: AMD FX-6300 3.5GHz 6-Core Processor ($109.99 @ Newegg)
Motherboard: Asus M5A78L-M/USB3 Micro ATX AM3+ Motherboard ($54.99 @ Micro Center)
Memory: A-Data XPG V1.0 8GB (2 x 4GB) DDR3-1600 Memory ($68.99 @ Amazon)
Storage: Seagate Barracuda 1TB 3.5" 7200RPM Internal Hard Drive ($52.92 @ Amazon)
Video Card: PowerColor Radeon R9 270 2GB TurboDuo Video Card ($129.99 @ Newegg)
Case: Thermaltake Commander MS-I ID ATX Mid Tower Case ($19.99 @ Micro Center)
Power Supply: Cooler Master Elite V2 550W ATX Power Supply ($39.99 @ Newegg)
Optical Drive: LG GH24NSB0 DVD/CD Writer ($15.98 @ OutletPC)
Operating System: Microsoft Windows 8.1 (OEM) (64-bit) ($89.98 @ OutletPC)
Total: $582.82
(Prices include shipping, taxes, and discounts when available.)
(Generated by PCPartPicker 2014-06-11 15:33 EDT-0400)
 
The motherboard uses a 2 generation old 760G chipset that was never designed to run an FX processor . It can , but its not ideal .
Instead pay a little extra and use a board with a 970 series chipset .

The asrock 970 extreme3
http://pcpartpicker.com/part/asrock-motherboard-970extreme3r20
or
Asus M5A97 R2.0
http://pcpartpicker.com/part/asus-motherboard-m5a97r20

The cm power supply is not suitable for use with a modern computer .
Use only 80+ bronze or better rated power supplies .
The Corsair CX 600 is $45
 
Solution


Is this PSU any good?
http://pcpartpicker.com/part/evga-power-supply-100b10500kr