I have exactly the same problem with opensuse 11.1 64bit.
EDID from my flat panel is not acquired correctly. Flat panel is LG L245WP, connected to Gainward GeForce 9800GT via DVi-HDMI cable. Xwindow should start in 1920x1200 native mode but instead it detects flat panel as HDTV and starts in HDMI 1080p mode. screen is shifted to top-left corner and looks really ugly. This is a known problem and can be overcomed in windows by tweaking .inf files to override wrong EDID information, but how to do this in Linux???
I tried the following:
- dump edid from flat panel on another box and use it - nothing changed
- disable edid and force using a modeline - mode rejected but should be ok
this is definitely a problem with nvidia drivers. my 2nd machine with an old GF 7600GT AGP card works perfectly well with this panel... this machine is running opensuse 10.3 32bit with nvidia driver 173.14.12.
also, if I switch back to opensource 'nv' driver, panel works perfect in 1920x1200.
edit: driver 177.82 installed by hand does not work either.