Display refreshing.

I'm having a problem with a computer in the display area.
Sitting without doing anything it's fine, But if i load my
MS Works or Streets & Trips, It starts to refresh the
display of the program. EX: If i'm typing in an address in
the address bar of Streets & Trips! It will refresh while
i'm typing and will erase anything i typed in. I have
tried to update the drivers for the display, That didn't
work, so i replaced the video card and that also didn't
work. This system does have a RAID setup, but i don't know
if that would be a problems.

Any help would be great.
Thanks
Joe