Dont think its your graphics card. before I upgraded my card the problems like the move, scale, rotate would only work in the persp window, and the move buttons in a ramp wouldn't work. Also hardware texturing and rendering were naff, and I couldent hardware render.

What version od the PLE have you got?

I had 6 and upgraded to 7 and then had loads of problems, none of the dynamics worked at all (particles, collisions etc).

Went back to 6 and no probs. It might be a problem with PLE 7 if thats the one your using??