what hardware for 100MB 3D files

Hi all. I have to deal with large to huge DTM dwg's. Our MIS dept.
seems to think an entry-level cpu and graphics card are good enough
(1.6ghz pIII/3dforce2 64mb). I do have 768 MB RAM. Am I off base in
thinking that a higher end system is going to make a big difference?
Does the graphics card need to have its' own OpenGL driver written for
AutoCAD? Thanks. donn