Originally Posted by slaWter
It shouldn't matter but apparently it does.
Yes I use PhysX and I like it. But there's no need for a dedicated card IMO.
It does matter. Window's needs to have DirectX rendering available on that card even though a monitor isn't hooked up. Consider my case where I have an external hooked to my 9800 GTX it has to render things with the card and use it for physx.
Consider playing Metro 2033 in windowed mode (if it has one)... what do you think would happen if I had a GTX 480 and dragged it from my monitor on the 480 to the 9800 GTX, while in DX11 mode.... no one knows, dividing by 0, can't happen. That's why it forces the lowest common DX mode available.
By using a card as a dedicated physx card that means you're dedicated all physx activity to that card.... not dedicated that card to physx. It still can, and will render video if you hooked up a monitor to it.