Star craft is a more CPU dependent game so I put more budget towards the CPU rather than the GPU.
This build fits the budget and has reliable hardware. I would have liked to fit an SSD in, but it wasn't a good idea because the cost of windows and the monitor.
http://pcpartpicker.com/p/p2qWBm
This will run starcraft at max settings at 1080 with no problems.
The monitor is a high quality 24" display. The case has good airflow and quiet design as well.