On a 17" Compaq s700 monitor connected to a Trident 985 video card
(I've had the same problem on numerous others, too), a light grey line
about a quarter inch wide keeps rolling from the bottom to the top of
the screen about every 5 seconds. I've changed the video settings to
numerous refresh rates and screen sizes and the problem stays pretty
much the same, except the roll rate changes a bit.
What causes this and how can it be fixed?