I had an IBM in a Electrical Generating Station that had a HUGE 480 volt 3 phase feed not far from the monitor in the next room. The display would swirl about 1

I had an IBM in a Electrical Generating Station that had a HUGE 480 volt 3 phase feed not far from the monitor in the next room. The display would swirl about 1/2 of an inch at quite a clip. The solution I picked was to put the machine in Text/Graphics mode (instead of normal character rom text mode, this was back in the MS-DOS days), so the vertical sync rate then matched up with the swirling EM fields, and there was almost zero apparent motion.