11.10 - Cannot access nvidia-settings or use HDMI with Quadro 3000m

I've just done a fresh install of oneiric on a Dell Precision m6600 with a nVidia Quadro 3000m. I can log in to Unity 3D, but if I try to start nvidia-settings, I'm told "you do not appear to be using the nVidia X driver". Also, HDMI out doesn't work.

The automatically generated xorg.conf is very short and doesn't appear to be using the nVidia driver:

Section "Device"
    Identifier  "Default Device"
    Option  "NoLogo"    "True"
EndSection

However, if I run nvidia-xconfig, it will replace the xorg.conf with, among other things, Driver "Nvidia" line, but when I restart the computer, lightdm won't even start at all.

This all occurs whether I activate nvidia-current or nvidia-current-updates by the "Additional Drivers" GUI. In either case, the GUI says "This driver is currently activated and in use". (obviously not).

How should I go about getting nvidia-settings and HDMI-out to work? Thanks!