Suggestion:

PCPartPicker part list / Price breakdown by merchant

CPU: *Intel Pentium G3420 3.2GHz Dual-Core Processor ($79.00 @ CPL Online)
Motherboard: *ASRock H81M-DGS Micro ATX LGA1150 Motherboard ($57.00 @ CPL Online)
Memory: *Patriot 4GB (1 x 4GB) DDR3-1600 Memory ($46.00 @ CPL Online)
Storage: *Western Digital Caviar Blue 1TB 3.5" 7200RPM Internal Hard Drive ($61.00 @ Centre Com)
Video Card: Gigabyte Radeon R7 260X 2GB Video Card ($145.00 @ PCCaseGear)
Case: Silverstone PS08B (Black) MicroATX Mid Tower Case ($45.00 @ CPL Online)
Power Supply: *Corsair CX 430W 80+ Bronze Certified Semi-Modular ATX Power Supply ($69.00 @ CPL Online)
Optical Drive: *LG GH24NSB0 DVD/CD Writer ($19.00 @ CPL Online)
Total: $521.00
Prices include shipping, taxes, and discounts when available
*Lowest price parts chosen from parametric criteria
Generated by PCPartPicker 2014-09-09 03:42 EST+1000

You will have to find a copy of Windows:

http://www.reddit.com/r/buildapc/com..._8_as_a_trial/