I’m working with 150 hours of footage. I’m using a dual 2 gigs G5, my RAM is 3 gigs and I have over 2 terrabytes on Lacie drives. I’ll cut down my timeline from 6 hours as has been suggested. I always have the activity monitor window open to watch the system memory and it seems fine. The only issue is that it makes me nervous to feel that I might be working for two hours or more only to have it crash.
Even though Autosave helps, it’s not reliable enough. I have it set for every ten minutes but I find that sometimes it skips and doesn’t save. Of course I’m trying to save manually as much as I can.