it depends on your resoultion and other settings, ect.
but i doubt it.
w/o a dedicated graphics card for physx, i doubt you'll be able to have it set on high.
The rest of the game, sure you should maintain 30-ish fps
You did not mention resolution, but for example 1680x you won't.
AA does not seem to make a big difference visually (read that in a review and agree) in this game, but it definitely takes fps away.
Me thinks on medium physX , and you do the trick with the cloth physX properties. Thats what I did, I just removed the cloth to test and it works nicely. http://physxinfo.com/news/3628/mafia-ii-demo-tweaking-p...
Resolution is the big question here: But to let you know..
My GTX 470 with 1920x1080 all settings maxed (High PhysX), with a Dedicated GTX 260 Core 216 for PhysX got me a "D" rating in the Mafia 2 Demo Benchmark utility. Obviously I'd get a better rating if I reduced settings some. But my point is to give you an idea.
At 1680 x 1050 with a single GTX 260, I would not recommend high settings plus PhysX. I'd suggest you turn PhysX off completely.