It worked! It worked!!! IT WORKED!!!!!!!!!!!!!!!!!!
As soon as I put
Option "ModeValidation" "NoDFPNativeResolutionCheck"
into xorg.conf, it started working!!!
Thanks a million, mate! I don't know what I'd do without your help.
If you remember, when I built another computer a few months ago and wanted to connect it to a plasma TV (it had a 8500GT chip) and had no luck at all with the nvidia drivers because of screwed up resolution, then I tried to install them with my Acer monitor I'm struggling with now, and also had no luck... I concluded the new drivers were stuffed. So, maybe I could have fixed my HDTV resolution problem the same way? If I only knew how at that time... Anyway, I'll try it again shortly.