let me take a shot at this... (please, someone correct me if i am wrong)
well theoretically, it is suposed to process the "physics" of the game. so instead of the graphics card "calculating" the physics of, lets say, a granade blowing someone up (that i threw
).
with a GPU alone, it will have to calculate the physics (based on the programing and such of the game).
with a GPU and a PhysX, The PhysX will calculate the physics, send the info to the GPU, and then the GPU will render it.
i think its a good idea, but its really unncessecsary because a normal graphics card CAN and WILL process it just fine... if not better right now.
im sure way back when people were talking about osmething like "man... why should we get this silly GPU when i can play pong on my brand new 1mhz computer?!"
technology is always changing... but new technology, much like a kid, needs time, money, and pressure...
lets just hope it doesnt make wrong choices and hang out with a bad group...