[s_forbes]

Have you tried running it without all of the graphics intensive display options? Get rid of the background image (options>colors - choose a plain color) and poke around through some of the other options to get rid of things you don't need.

I ran Solidworks for a few years on a 1.5Ghz Intel dual core with 1 gig of RAM (XP) and was able to build some pretty complex models without issue.