Sectorgame

I've been digging around the driver settings for my GF4MX 420 and have a few questions about some of the settings.

What do the NULL PS x.x check boxes do? It's under the Performance Analysis section of "More Direct3D". Also, how many frames should I set it to render ahead?

I used to have an MX440, the PS X.X is, I think to disable pixel shading emulation or the like, which the GeForce4 doesn't support in hardware anyway. As for rendering ahead, I've no idea, as far as I know, 1 is the fastest bet.

So would enabling PS blah blah NULL equate to any speed increase?