I mostly want to get he 450 so I can fold while I game. And is there really any games that benefit Physx? I literally JUST got my 465 a few weeks ago and it preforms admirably in games it's just bottlenecked by my CPU and RAM.
There are more, but I can't really think of them right now.
No offense, but why did you get a 465 a week ago? Was it a bargain? Because there are better cards out there for the money, and cheaper.