On Tue, 2020-05-26 at 18:56 -0500, Michael Hennebry wrote:
> VESA notices several resolutionns,
> including 1024x768 and 800x600 .
> I really do not understand why none of them are allowed.

As a general answer, the system checks out what the graphics chipset
can produce, and what the monitor supports, and will only make use of
mutually compatible modes.  It doesn't just look at the resolution, it
also looks at the scan rates (or pixel frequencies, for modern screen
types that don't really scan).