Compiz + Xinerama + Nvidia?

[Schalken]

How do I enable Compiz with Xinerama on my Nvidia card, with nvidia-glx-new?

Compiz works fine without Xinerama, but as soon as I enable the second screen and try to enable Compiz I get the error "The composite extension is not avaliable." Googling for said error returns a bunch of cases with ATI cards!

[kpkeerthi]

The binary nvidia driver supports multiple displays natively. You need nvidia-settings installed from the repository

1. Install nvidia-settings
sudo aptitude install nvidia-settings

2. Launch nvidia-settings from command line
gksudo nvidia-settings

3. Click on 'Detect Displays' and choose the display mode (clone.right-of, left-of, etc)

Optionally if you want to make the change permanent, click on 'Save to Xorg.conf'

[Schalken]

Yup, thats exactly how I'm enabling Xinerama in the first place.

[_DD_]

With the nvidia drivers you need to enable twinview rather than Xinerama - Xinerama doesn't support the right extensions needed to run Compiz.

[Forlong]

https://help.ubuntu.com/community/XineramaHowTo

There's a guide how to use TwinView

[Schalken]

But TwinView makes my GNOME desktop span both displays - like, the panel goes all across the top spanning both displays and half my bottom panel is visible on the bottom of the taller display (the other half of the panel is hidden in dead area below the shorter display). Fullscreen apps cover both displays as well.

That's not the way it is in either Mac OSX nor Windows, and it's quite ugly. :(

[Schalken]

Aha! If I restart the X server after enabling TwinView, then my window manager grabs display positioning information and correctly puts the gnome-panel and fullscreen windows on just one display. :)

But, just like with real Xinerama, I have to logout and back in when I plug/unplug the external display to achieve this. :(

Oh nVidia, when will you finally support XRandR 1.2?

Thanks for your help.

[RAOF]

...
Oh nVidia, when will you finally support XRandR 1.2?
...

Never, apparently. They'll possibly/hopefully support XRandR 1.3, which will include support for multi-card.

[Schalken]

Great. And I just found out the reason why Compiz is so choppy on this thing: NVidia's driver enables PowerMizer which underclocks your chip until you give it the load typical of a game. And we can't turn it off either. Not without hacking the xorg.conf or some random module configuration file with an abstraction over the kernel module's understanding of the Windows registry.

Yes! The Windows registry! Nvidia's xorg.conf options are an abstraction of the windows registry!

I bought your hardware and this is the treatment I get?

Nvidia I hate you.