I've had the Dell myself, and I believe that it gives bogus DDC-data.. Could you try running without xorg.conf with herd5, to see if the xserver manages to get the correct data out of the monitor.
-- Dell 2405FPW and resolution 1920x1200 https://launchpad.net/bugs/40422 -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
