Hi!
I have a Radeon 9600 in one of the computers where I have installed PS and yes, I got some problems (first FPS 1.0 and after the text disappearing).
I guess that NVidia, as people as said above, handle better than Ati OpenGL, but even if, I have tried to run the game in software renderer when I was having the FPS=1 problems without big results.
I have JUST installed the new drivers and fix the .dll problem, and this has assured me no problems during game.
Ary