can't comment on mac versions (since i didn't have any on my dsk so far) - thinking about how it is done on windows i'd assume it will use its own memory space.
memory - well, on the 4 GB PC ~ 3.2 GB have been left to the system, 1 GB was used by windows, and we have not been able to load all three mic positions into the remaining 2.2 GB - sorry, but i can't remember how much memory exactly one mic position needed.
christian
and remember: only a CRAY can run an endless loop in just three seconds.