it could have been the problem but even so 512 should be enough to run VPC and ONE program, but who knows. spec wise i was running it on a PB G4 1.33Ghz 1.25Gb RAM. so its not quite a G5 but i wouldn't expect much better on a G5. but i didn't try to download to the MD sorry, i wasn't ever planning to, i got this unit as bootlegging device only, my iPod will remain my music player. oh and also there were no other apps open in OSX no other programs open in Windows except SS, so nothing else was draining juice from my CPU or RAM.