It makes a HUGE difference. One drive for software, a seperate one for audio and definitely a seperate one for video. I run two SATA drives, purposefully limited to 80GB each, one for Audio, and one for Video, which are my "work" areas. They are kept clear of anything other than work in progress. Anything not currently being worked on gets moved off to one of my firewire drives. This setup works beautifully - you get easy playback of everything, PT runs lightening fast, and you don't get buffer problems, or stuttering video playback. Of course, a Dual Core and more RAM than you think you'll ever need, work great. Alan