To whom it might concern, I recently got ahold of a copy of vitualpc ver 4 and loaded it on an Ibook. The Ibook had in computer 128 and an added 256 of memory. It's processor was a g3 600mhz. The computer ran the show but seemed to suffer from the slower processor problems as do pc's. A larger ram card was even tried but did not make any difference. The only problem was that the 'fades' got that notchy layer thing happening and that the other effects were a bit jerky as well. There were no problems with the music or sound sychronization. With no transitions selected, it ran the smoothest. I was told that a more recent version of virtualpc would run more smoothly. From my experience running shows on other pc's and the threads in this forum I still think it is a processing speed thing.