2 Video Cards -- Disable Open GL on single?

[amites]

Found myself on a steep learning curve with Nvidia hardware and linux

I have 2 cards trying to support 3 monitors

Card 1: GeForce GT 520 1GB

Card 2: GeForce 8600 GT 512MB

Didn't learn until after ordering card 2 that there is a gap in compatibility between series 8+ cards and before the 8 series when it comes to rendering OpenGL together

Having learned this I'm now trying to disable OpenGL support on just card 2 while keeping it on Card 1 so that I can run Gnome 3 -- is this possible?
Right now the setup has xinerama running all screens as a single desktop -- happy to turn the 3rd into a separate desktop but can't figure out how to get composite disabled on a single screen and/or device

xorg.conf and Xorg.0.log pasted at
http://pastie.org/3985583

[amites]

As an alternative I'm curious if replacing the GeForce GT 520 with another card that is also in the 8+ series would make things run smoothly?

[Plagman]

Both of these cards are in the 8+ series. What problem are you seeing exactly?

[sleepguide101]

Any suggestion for Shader model 3.0?

[amites]

Plagman: I wrote out a more detailed writeup on AskUbuntu

good to know that the GT 520 is in the 8+ series saves me from buying another card

the forum link is http://askubuntu.com/questions/14299...t171413_142990

I am getting an error in Xorg.0.log that is referenced at
http://us.download.nvidia.com/XFree8...hapter-14.html

[ 23.208] (II) NVIDIA(1): Setting mode "nvidia-auto-select+0+0"
[ 23.254] (WW) NVIDIA(1): The GPU driving screen 1 is incompatible with the rest of the
[ 23.254] (WW) NVIDIA(1): GPUs composing the desktop. OpenGL rendering will be
[ 23.254] (WW) NVIDIA(1): disabled on screen 1.

(OpenGL is disabled on all screens)


the specific error is that I cannot use anything with OpenGL -- GLX-Dock / Gnome 3 / etc...

single card with 2 monitors still works great but as soon as I enable the 2nd card and reboot then the only workable alternative seems to be using KDE or Unity 2D for the moment since they both allow the CPU to make up for the GPU though there are significant draw backs to this

currently using Xinerama to turn 3 screens into a single desktop -- originally tried using Twinview on 1 and a separate desktop on the 3rd but ran into similar issues there where OpenGL would not function

any ideas are appreciated -- gone through 10 variations of Xorg.conf manually and using nvidia-settings without any luck thus far

[AaronP]

The GeForce GT 520 is from the Fermi family of chips and the 8600 is from the previous family, so that explains the mismatch. How exactly is OpenGL failing on screens 0 and 2?

To disable Composite, you need to put the option in its own top-level "Extensions" section, not a SubSection of a screen. You can't disable it on just one screen and not another because extensions are server-wide.