I upgraded my Dell Latitude to XP, and the multimonitor function no longer works. I can use either an external monitor, or the bulit-in one, but not both for multiwindows. I believe i need to upgrade my drivers, can't find updated drivers. Can anyone help

Latitude CS 400XT
NeoMagic MagicGraph256zx driver 3.8212890625Mb

TIA,
Steve