Yeah.... You 'can' build one for under 1K, but that's using second rate parts.
Just going to leave this here for Slade...
http://answers.yahoo.com/question/index?qid=20110526194730AApkQml
"Average gaming PC with the latest specs costs around 1K if you build it yourself.
Also...
http://www.amazon.com/Microtel-Computer®-AMTI9028-Computer-Microsoft/dp/B003IS5N4O/ref=sr_1_6?ie=UTF8&qid=1379362078&sr=8-6&keywords=gaming pc
My friend Chris is selling his Liquid Cooling hypertech PC with optimized RAM + Cooling systems + 64 bits Graphic's Card with the highest performance, and a whopping 32 Gigs of RAM... All for $2,400.
Nice job looking like a fool Slade by showing a graphics card cost only $72 when the high end ones cost about $100-120. Besides, the standard issue Gaming PC (WITHOUT any modifications) STILL costs more than an Xbox One around $600, and you need to take the time for utility and optimization. And those aren't even the high-end Microtel models.
In 2 years your gaming PC will be outdated, assuming the great console titles for PS4 and XB1 even get ported for PC gamers.... Good luck!!! xDD