800$ computer- Good Category

http://www.amazon.com/iBUYPOWER-Gamer-Power-AM591SLC-Cooling/dp/tech-data/B0051U114I/ref=de_a_smtd

 

will need monitor

http://www.tigerdirect.com/applications/category/category_slc.asp?CatId=2388&SRCCODE=WEBGOOMON&cm_mmc_o=mH4CjC7BBTkwCjCECjCE