Do you have a 1080p or a 1440p monitor?
But anyway for 800 you can get something like this:
http://pcpartpicker.com/p/9CtbFT - Base Total: $802.69
But you wont be able to play all games at high settings @1080p. In some titles you have to settle for medium settings in order to hit that 60fps.
If you really want to play all games at high settings you need to add another 100 dollar to your budget and get the gtx 970.