[ddingus]

There were failure modes they didn't always think about.

I once killed off an 80's era TV I was using for a display on a microcontroller. At the time, I was writing low level NTSC driver code, and was abusing the standard a little for some color advantages.

A combination of bright screens, overly dark ones ( sync in the visible raster), and misplaced vertical blank pulses popped that TV. It never displayed the same again.

Still worked, but was just crappy.

As monitors age, they can become vulnerable to this kind of thing. Not so much a single value, or poke, but ugly code intended to stress a display could take a few of the edge case ones out.