so i wanted to upgrade that im willing to spend 200$-300$ if you wanna kno my specs let me know.
i play counter strike source, Garry's mod, mine craft, grand theft auto iv, and gta five when it comes out, um im gonna buy battlefield 3, maybe modern warfare 3
id like to play on high on medium settings.
can you tell us which games you play the most? It's not a bad choice to pick up a second 6850 if you have enough power, given that 2 lesser cards often outrun a better card for the same amount of money. If you are decided to go with 1 card for simplicity, I suggest you wait till the cheaper 6XX cards come out, or get 7850, which is basically the 7XXX version of your card.
I would for sure look into the AMD 7xxx series. I will link you to the 7xxx series and show you a bench mark. This is with in your budget and you can see how much of a difference it is between the two. Good luck to you on this.