how much rdram needed

this is a question for a friend who is building a new computer. She does video editing(Premeire, sound editing) as well as a great deal of photoshop and some maya. Although this is maybe subject to opinion, is it necessary for her to get 1gig 4x256 rdram instead of 2x256. Will she ever see the difference?

with video editing the more ram the better, i have 1.5gb RDRAM and it Pwns

what kind of ram, 800 or 1066

i have 800, if you can afford 1066 go for that.