Blank primary monitor on oneiric, only output on external monitor. (NVIDIA 8400M GS)

[BicyclerBoy]

If it ain't broken you haven't tried fixing it enough!

AFAIK. The nVidia driver only supports one X server per GPU; multiple X screens not X servers. So same desktop manager.
Don't know what unity looks like on 2 screens.

You can not place icons on 2nd screen (not since 8.04), can not drag items between screens. Can move the mouse.

Can force apps to launch on either screen:
DISPLAY=":0.1" vlc
will launch vlc on 2nd X screen

[Jarige]

Well today I hardly booted Ubuntu, but all went well today. There was one point where I accidentally booted Ubuntu instead of Vista, at that point the screen was at the secondary monitor. But after rebooting the screen was back to the primary laptop monitor.

It feels kind of random as to when it happens, but it seems to happen most after Unity crashes (or X crashes), very weird.