[pansa2]

> 4:3, so 1280x1024

That’s 5:4. The correct 4:3 resolution is indeed 1280x960.

[pavlov]

That’s true, but for some reason, in mid-1990s operating systems, the step up from 1024x768 was usually 1280x1024.

Maybe there was a popular professional monitor at some point that was 5:4 and had this resolution?

[kcb]

Many of the first popular LCD monitors were 17" or 19" 5:4 1280x1024.

[pavlov]

But that came after 1280x1024 had already been a popular resolution for a decade.

What was the original 5:4 CRT that gave us this resolution?

[TylerE]

There isn't one. Running a non 4:3 CRT mode simply resulted in a change in aspect ratio. However, by adjusting the geometry in the settings menu get to something closer to the aspect ratio by using the marginal areas of the tube. Pincushion will be a bit worse, but who cares,