Garbled Viewport in SWKS 2004 SP0

I've seen strange things displayed in SolidWorks over the years, but
nothing quite like the following (in 2004, SP0):

Opening up the first assembly or part presents no graphics problem;
however, when a second or subsequent files are opened, the viewport
(not the entire SWKS screen) displays either badly clipped and
fragmented components or is filled completely with small rectangles of
multi-colored dots.

It turns out that ALL I have to do to correct the problem is to drag
the right-hand vertical border of the Feature Manager a slight
distance. (Afterwards, the offending file continues to display with NO
problem - even with multiple tiled windows.)

For the record, the graphics card (nVidia GeForce FX 5600 Ultra)is not
on the "approved" list and perhaps the hardware or drivers are at
fault; however, I'm curious to see if upgrading to SP2.1 will fix the
erratic behavior that could be caused by SolidWorks itself?!

Have others seen this type of viewport-specific display glitch?

Per O. Hoel