TressFX is a GPU compute thing, not related to the CPU. Though would turn it off anyway, the 7750 isnt exactly a powerhouse and that GPU grunt can go toward other things.
The rest I believe is all GPU.
Disable PhysX in games, that simple. Though chances are since you dont have an Nvidia card, it just wont even enable it or give you the option unless (I think, not sure on this) you have the CPU driven PhysX drivers.