So given all the ways you can mix and match, it's hard for me to pinpoint a single usage model that a consumer would know what to go buy, because there's so many variables, and so many configurations you could actually come up with.

GO: I was thinking more in terms of the actual effects themselves. What are all the things that change if I can have two GPUs as opposed to one? Two GPUs give me more PhysX than one GPU, okay, but what is that "more" equal to? I suppose that's going to be game specific?

BDR: Yeah, it would be.

GO: It's easier when you having something like AA or AF [] or revisions like 2.0 or 3.0, because while you don't know precisely what the end result is, there's consensus on what it adds in general terms. It'd be interesting if you guys could come up with a PhysX rating of some sort.

BDR: Maybe, but it's hard to do that because you have people playing at different resolutions. They've got different monitors, different screen sizes, refresh rates, all that kind of stuff. So the permutations of all the different kinds of configurations out there, there's just so many. It's really hard to pinpoint experiential stuff.