Probably not in PQ, but the integrated is likely slower... don't know if it's slower enough to make any difference, however.
gnome, it's not what I'm talking about... I mean how to calculate the Mb of RAM needed to display a given risolution on screen, e.g. 1280* 1024 and 16 bit resolution -- and so knowing whether 32 Mb per head are enough (or, instead, the driver will look for the Turbocharges routines in order to grasp some RAM from the system).
I never saw a calculation for the "amount of RAM used relative to resolution"... but 32 mb/port is waaaayyyyy plenty. I used to run my same setup on Win2K with only 4mb per port, and it ran the same as my rig today.