Well, that ends up getting my screen to have a bunch of lines through it, staggered -- so I'm not much better off than I was before. I'm guessing that's an nVidia driver issue or something. If I had any idea about video devices, I'd try to fix it, but I don't. I'll just live with a bit low-res VESA for now (all of the VESA modes don't seem to work), unless someone has ideas.
Thanks! --dho