$300 gaming pc

http://pcpartpicker.com/p/BGHm

fight me build a pc

also it could be a $350 gaming pc and could have a 6670 but its your call

not running an afermarket Power supply? those case power supplies most of the time are junk, would be a shame to have a nice new set up fry, all because of a $10 PSU. please reconsider, or just wait until you have a $100 more to spend.

a 6670 is pretty good for running most modern games at low-medium settings, if you could afford more, i would suggest a better card. like a 7750 or something. after the mail in rebate it would be $15 more than a 6670, and more powerful.

http://www.newegg.com/Product/Product.aspx?Item=N82E16814127709

If you can afford like 25 more dollars, spring for 1866mhz 8gb memory. You need as much memory and the fastest you can get since your graphics will be sharing the onboard memory with the rest of the system.