Open Challenge to Nvidia developers and linux community

Graphics / Linux Linux
1

Take 3 NVidia cards GT 640 cards in my case.
Stick them in a PC - No SLI
Add two 23" LCD/LED screens per card for total of 6 screens.

Install Ubuntu (14.04 now, but had same problem with every version after 7.04)

Get the following to work:
Maximize windows per screen (not one big window over all the screens)
Be able to drag a window from one screen to another.
Have hardware acceleration. - have something like 3D Desktop cube or any compiz effects working.
Post detailed instructions how to accomplish said feat.

I double dare anyone to do this.

Pro tip: It can not be done.

My best effort:
6 separate x displays combined into one screen (5760x2160)
No hardware acceleration.

xrandr -v
xrandr program version       1.4.1
RandR extension missing

Disabling xinerama - full hardware support, can play games etc. but not move a window from one screen to another.

2

No kidding. It’s not a supported feature and they’re pretty clear about this in their documentation.

3

Well, I think it can be done. Without RandR though, but you will have openGL hardware acceleration across all screens / devices.

If you’re interested in that, I can post my xorg.conf and the changes I made to Xinerama.c.

Yours

Paul

4

You can accomplish what you want with nouveau and Randr 1.4 provider objects

5

If you could point me towards some detailed documentation I would be happy. The Randr documentation is a bit limited and generalized.

6

I would love to take a look at your xorg.conf and the changes to Xinerama.c

7

Update:
Using randr with Nouveau driver I managed to get 4 of my 6 screens working.

Command for 4 screens:

xrandr --output VGA-1 --mode 1920x1080 --pos 1920x0 --rotate normal --output DVI-D-1-2 --mode 1920x1080 --pos 0x0 --rotate normal --output VGA-1-2 --off --output HDMI-2-3 --off --output DVI-D-1 --mode 1920x1080 --pos 1920x1080 --rotate normal --output HDMI-1-2 --off --output HDMI-1 --off --output DVI-D-2-3 --mode 1920x1080 --pos 0x1080 --rotate normal --output VGA-2-3 --off

Command for 6 screens:

xrandr --output VGA-1 --mode 1920x1080 --pos 1920x0 --rotate normal --output DVI-D-1-2 --mode 1920x1080 --pos 0x0 --rotate normal --output VGA-1-2 --mode 1920x1080 --pos 3840x1080 --rotate normal --output HDMI-2-3 --off --output DVI-D-1 --mode 1920x1080 --pos 1920x1080 --rotate normal --output HDMI-1-2 --off --output HDMI-1 --off --output DVI-D-2-3 --mode 1920x1080 --pos 0x1080 --rotate normal --output VGA-2-3 --mode 1920x1080 --pos 3840x0 --rotate normal

This outputs:

xrandr: Configure crtc 5 failed

And drops me back to two screens.

The whole process is a bit of a pain, constantly crashing compiz, so I switched to Openbox for testing.

8

After extended testing, trial and error and a lot of frustration, I am back to using xinerama and the latest nvidia drivers with openbox and Composite set to Disable in my xorg.conf file.

For the first time in 8 years, I am seriously thinking about installing windows again on my work pc, and running linux in virtualbox.

It is really disappointing that nobody can get something like this to word as easily on linux as it does on windows.