Whats the issue with this?
I have had the same issue - all cpu work keeps getting computation errors (so I just aborted all of it) - I'm using WinXP with 4Gb Ram (3Gb due to 32bit OS).
Any solutions?
First things first - are you running einstein as that is a complete memory hog
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You have more RAM than me, so should be alright, since stopping all unused processes, turning off aero, increasing the disk cache - things have been a bit better...