Attached Link: http://www.avsforum.com/avs-vb/showthread.php?t=805921

Sounds like it's down to the graphic card/driver settings.

If you go to the NVidia control panel there should be an option to "manage custom timings" or similar .

If you check the HDTV  box and enable 60Hz you should be able to force a 1920x1080p setting on the graphic card.
I can't give you any more details as my 8800GTcard is currently connected to a standard P'n'P monitor and won't allow me play too much. 

1900x1200 won't harm the TV, it just rescales it to 1900x1080 and causes the text to look poor. 

Edit: attached link may help.