PhysX is aimed at running on current generation 'consumer grade' gaming hardware, so think a GPU you can get for $200 (if not less). It works out of the box on all of NVIDIA's modern graphics cards.
Of course, you do have the problem of what to do when the water sim uses up all the available GPU compute power and bandwidth - not much left to render, in that case...
Of course, you do have the problem of what to do when the water sim uses up all the available GPU compute power and bandwidth - not much left to render, in that case...