I have three CRT monitors but this one is oldest and maybe most interesting. It seems to have no geometry adjustment settings but that's ok for now because the geometry is very good. This monitor came with a mail order 386 my family bought in 1991. Never had any issues with it. Unfortunately the image doesn't display all the way to the plastic bezel, no matter the resolution there's always a good half inch square border between the bezel and the displayed image. It can do 640x480, but I'm not sure if it can go 800x600. Kinda don't want to test that in case it lets out the magic smoke. It's doing fine with my 386 where it's permanently on lower resolutions anyway. I'd hate to lose it.
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Here you can see the constant black border since the image does not fill the screen. I don't think anything's breaking down, I don't think it ever filled the screen.
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