Here you go, this is a great setup that will last you at least 3 years on high to medium level detail in games. also type into the search bar here on the site and type in 1200 build and youll see that many people have the same kind of questions, so it would be good to read a few entries to learn about the parts you want to get and the level of performance you will get with that kind of budget!
PCPartPicker part list:
http://pcpartpicker.com/p/3E0q9
Price breakdown by merchant: http://pcpartpicker.com/p/3E0q9/by_merchant/
Benchmarks: http://pcpartpicker.com/p/3E0q9/benchmarks/
CPU: Intel Core i5-4670K 3.4GHz Quad-Core Processor ($229.99 @ NCIX US)
CPU Cooler: Cooler Master Hyper 212 EVO 82.9 CFM Sleeve Bearing CPU Cooler ($29.94 @ OutletPC)
Motherboard: Asus GRYPHON Z87 Micro ATX LGA1150 Motherboard ($154.99 @ NCIX US)
Memory: G.Skill Ripjaws X Series 8GB (2 x 4GB) DDR3-1866 Memory ($84.99 @ Newegg)
Storage: Sandisk Ultra Plus 64GB 2.5" Solid State Disk ($64.99 @ Micro Center)
Storage: Western Digital BLACK SERIES 1TB 3.5" 7200RPM Internal Hard Drive ($79.98 @ OutletPC)
Video Card: Gigabyte Radeon R9 280 3GB WINDFORCE Video Card ($279.99 @ Newegg)
Case: Cooler Master N200 MicroATX Mid Tower Case ($43.99 @ NCIX US)
Power Supply: SeaSonic G 550W 80+ Gold Certified Semi-Modular ATX Power Supply ($79.99 @ Amazon)
Optical Drive: Samsung SH-224DB/BEBE DVD/CD Writer ($14.99 @ Newegg)
Operating System: Microsoft Windows 8.1 Pro (OEM) (64-bit) ($129.99 @ Amazon)
Total: $1193.83
(Prices include shipping, taxes, and discounts when available.)
(Generated by PCPartPicker 2014-05-04 20:06 EDT-0400)
And as you asked right around 1200$
hope this helps!