That goes into how they work, if a programme runs on only one core (although when rendering maya will use all aviilable cores and processors) if you have a dual core 2.2 gig processor and its only running on one core your only getting 2.2gig, if you have a single core 3.2 gig processor it will run faster, untill you need to use the power of both cores.

So if your G4 or whaever has a faster clock speed (relavant to the intels as they run different architecture that apple dropped) then you probably would see a difference.

Although, in general useage, modeling etc, I doubt you would see much of a difference at all, only when it comes to running simulations for particles and dynamics.

Whats the specs on your other PC?