If you can scrape up $500+, here is a decent rig that you can assemble that will last you quite awhile or can be upgradeable in the future if necessary. Needs an OS though.Newegg sells good stuff and is known for their excellent customer service. Good luck whichever direction you take.
http://www.newegg.com/Product/ComboBundleDetails.aspx?ItemList=Combo.1231493
http://www.newegg.com/Product/ComboBundleDetails.aspx?ItemList=Combo.1231493