Heres why i think Physx is unecessary. For 1, as stated, you can turn it off if you really want to. 2, it takes a game from looking perhaps not detailed enough from a birdseye view you cant get, to making it excessively unrealistic. Sometimes it looks better, but even then, its always unrealistic. If you watch the mafia 2 physx vs no physx, it looks like shooting bullets you cant see with no physx, to shooting rocks out of your gun. 3, its not used in most games, and others dont use it extensively. 5, only some video cards do it, and i get plenty enjoyable gaming on my 4890 without it. Nice, in a few occasions, yes, worth getting a possibly inferior card, NO.