well when i read that
I somehow find you are even nice on the budget with 300$.
Quite simply put there is no card on the market and I mean it NO CARD whatever CPU it is paired with that can run demanding modern games at full detail full HD rez and 85 Fps steady, (not even factoring sterescopic vision)
Now there are games STR where you don’t need 85+ Hz and 85+.
So i would rather say that you ll need to be reasonable on the eye candy most of it like Anisotropic filtering and antialiasing has very little need to be put full blown,
I dare anyone here to see any diffrence on any game between full HD AA 2X and AA 8x at 30" distance on anything smaller than a 24" diagonal , anisotropic filtering is game dependant , on SFIV for example there is no perceptible difference between AF4X and AF16X.
As a budget comparison a 4 year old dual core will run SFIV at
60Hz steady with acceptable detail with a 90$ VGA,
60Hz steady maximum perceptible eye candy + stereoscopic 3D with a 200$ VGA,
60Hz steady full (overthetop) detail stereoscopic you’ll need to resort to a 450$ VGA.
World in conflict is about the same as SFIV but you ll need a better CPU and you ll have a very decent 40 FPS with the same budget.
Games like modern Shooters same budget for offline non-competitive gaming full eye candy, or comeptitive gaming with pragmatic gaphics,
around 700$ with a pair of VGA card ( implying even extra money spent on adequate CPU and PSU and heat exhaust) for both full eye candy and competition compliant FPS rate.