PhysX blows, forget about it, the only reason AMD isn't having it is that NSHVidia doesn't like to share. You may also blame game developers for being too lazy to implement more cpu physics, you don't really need a gpu doing that job. And finally.. PhysX renders client side only, so in (mostly) multiplayer games like Arma III, you will see things that others don't for that extra bit of cunfusion and eye candy.
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