In the past, Nvidia cards had support a 3rd party program called nHancer, which gave Nvidia cards an unofficial form of supersampling AA. This worked great in many situations, if you had the graphics power.
Unfortunately, nHancer has not been updated to work with drivers in the 200's (over 6 months), and I'm not sure it ever will get updated again. Does anyone know of any other way to get Supersampling AA for Nvidia cards?
I think you can force Supersampling (among other forms of AA) through the driver control panel.
Nvidia does not have this support in the control panel. It does have "Antialiasing - Transparency" Supersampling, but that does not work the same way as the "Antailising - Setting" supersampling. There is a rather large disparity in image quality.
Its been a while since I used a NVIDIA card, so you'll probably need to talk to someone who actually has one. I know supersampling is still supported (it was tested by anandtech for the 580 GTX), I just don't know where to enable it.
I did a few searches and reads, including anandtech's review, and it appears the closest I could find out about an official SSAA is they were speculating thaty they'd have either SSAA or a combonation of SSAA and MSAA with the new gtx580 before it was released. It appears as though they still don't have an official version.
For now, I've decided to use the older drivers, which has terrible performance (it was the first set of drivers that worked for the 470). Dragon Age: Origins isn't too demanding, so it seems fine. I'll just have to update drivers for more demanding games later.
The big deal on SSAA is that it fixes aliasing on the entire scene, not just around objects. This is usually most notable when you see fields of grass with lots of jaggies on the blades and in trees, as these are in the textures, and not around objects. MSAA only fixes jaggies around objects. SSAA fixes them all.
ATI's HD 5xxx and 6xxx cards actually have super sampling, which do look quite impressive when used. I'm not sure why Nvidia is so reluctant to give it to the public. nHancer has been allowing it for years for Nvidia cards.