GUI Boxes/Buttons all gone blank !? HELP

One of our Windows2000 users with Dell CPi Laptop is experiencing some bizare problems. About 70% of the time all the GUI boxes/buttons are blank, or are drawn incorrectly. This make trying to use Dial-Up or anything almost impossible as they dont know which buttons to click as they are blank!. Even right clicking on a shortcut, clicking onto Properties brings up a Blank window. No text, tick boxes, shortcut path etc.. All gone. Totaly blank grey pane.
Ive tried reinstalling SP2 and DirectX.
Anybody have any other ideas ?
Thanks 🙁