Comment 2 for bug 894132

I tried it. unity --reset appears to kinda sorta work and start Unity 3D. However it is unusable, and logging in with it still doesn't work.

The first time I tried it Xinerama was still enabled. This resulted in three mirrored copies of Unity, one on each monitor (which all acted as if I clicked on them, any time I clicked on one of them). The desktop background image was shifted to the right, and the mouse didn't click where the mouse cursor was displayed, but one screen-width to the right, which was extremely confusing and unusable.

I then tried again with Xinerama disabled. This time it looked a bit better. However it only used my middle monitor. The left and right monitors just displayed a white screen with a menu bar on top (apparently a Nautilus menu bar) and no way to start programs. Again, unusable. Also because since the mouse cursor does not stop at the left edge of the middle screen it is *extremely* hard to get the Unity panel to pop up.

None of this made any difference to logging in to a Unity 3D session directly. That still didn't work, only displaying a menu bar (from Nautilus, presumably) at the top of every monitor with no way to start programs or even log out.

Man, multi monitor support gets worse with every release of Ubuntu. It has now gotten to the point where it is unusable on *every* combination of display driver or session. The only one that works at all (with all monitors) is GNOME Classic (No Effects), with Xinerama enabled, but even that doesn't work right. When I try to drag icons on the desktop, the icons are suddenly transposed a full screen width to the left of the mouse cursor!

What a terrible mess. Is Ubuntu even tested on multiple monitors at all? Here is the long list of failures of Ubuntu to allow me to use all the monitors on my system:

* I have to use the proprietary NVidia driver because the open source driver does not support multiple cards.
* I have to use Xinerama because otherwise there is no way of combining all screens into one desktop and be able to drag windows from one screen to another. (Previous versions did at least work without Xinerama, with each screen acting as a separate desktop, but that is no longer the case in this version.)
* When Xinerama is enabled the ONLY session that works somewhat correctly is GNOME Classic (No Effects). Every other one either will not start at all, or has horrible bugs with mouse positioning, window placement, unusable second and third screen, etc.
* And even that doesn't work fully correctly, as described above.

And this is not some exotic or ancient system. It's a modern PC with a 3 GHz quad core Intel processor, 8 GB of RAM and two NVidia Geforce 8800 GTX cards, two monitors on the first card and one on the second. Something which Ubuntu should comfortably support.