I do not understand why there is so much problems with people running 7600GT cards.
When I installed Elyssa one of the first things IT did once it was running was invite me to install the new restricted driver specifically for Nvidia cards.
It did this because it had detected the card if I understand correctly. No need to go to synaptic and search, it just basically said you need this and went ahead and installed it when I clicked my consent.
Maybe I am one of the lucky ones but I have to say it couldn't get much simpler than that.
The only problem I have had is with it running Flightgear and I am not so sure its the cards fault as it runs at first opening but suffers slowdown and a lose of controls and part of the screen after the first flight,
Anyway I digress.
Go to control center and click on hardware drivers. There should be an Nvidia accelerated graphics driver in there under proprietry drivers. Next enable it. If it isn't there it will be in synaptic.
Good luck with it and all the best.
Sorry Guys maybe I should have put this in the other thread