You know the numbers on your card already - 7600 - this is a good start.
Now, divide this number by the size of your screen in inches - maybe 22 or something like that.
Then divide it again by the refresh rate - for LCDs use 60 - I kniow technically there isn't one, but this is why the XP and Vista display properties still quote 60.
Now, there is no need to actually play the game to see the fps, just look at the cover. There are normally some numbers on it, i.e. Half Life 2. Multiply your previous answer by this figure.
Add on to this the price of the game you wish to benchmark (in US $ only) and voila, there's your FPS calculation.
Some will tell you that this is incorrect, however they're all wrong. Everyone knows that a sequel or last part of trilogy uis better developed and runs more smoothly. that's why you get higher FPS - a higher number on the box.