Dying Monitors

Archived from groups: comp.sys.ibm.pc.hardware.video (More info?)

A family member has had 3 monitors fail in the last few months. The first
was the original monitor that came with the Dell system about 5 years ago.
The next 2 were also older used monitors that were given to them. I haven't
seen the situation, but they say they die slowly - the screen apparently
gets jittery and then worsens and finally dies. Apparently they've all died
in the same manner.

Any ideas what could be causing it, or how to determine what's going on?

1) the computer is doing it somehow?
2) there is an electrical problem perhaps?
3) pure coincidence?

It's a PIII 533 with XP home edition and has, I think, a GeForce 2 of some
kind that I upgraded for them a couple years ago.