Re: X won't start w/ best available resolution...
Ok, almost there!
AaronP was right on about the Gnome Screen Resolution preference. When I set that, the system now logs me in at 1920x1080.
Here's the one remaining weirdness....which I'm happy to live with, by the way.....
When I login, my monitor says "1080i", which I I thought was strange. What's even stranger, when I start mythfrontend, the monitor blanks, then comes back as "1080p"....??
Any idea on that one?
Anyhow, as I said, I can live with that, I'm just happy that I can login at the correct resolution.
To Leech: I think our issues are totally separate. To my knowledge, my problem was w/ the Gnome Screen Resolution preference resetting my resolution from 1920x1080 down to 1024x768. I don't have any overscan issues or anything else. For me, 1920x1080 always worked perfectly, except that I couldn't automatically get that resolution on login. Now I can. I think the issue you describe is quite different.
Thanks again to AaronP!