Doubt on precedence of xorg.conf over xorg.conf.d

I’ve read the how-tos (thank you oldcpu!) and wikis about how xorg.conf take precedence over the section configuration files in etc/X11/xorg.conf.d/, if it exist.

I also understand that the xorg.conf can be partial. If it is missing some sections, these will be taken from the corresponding xorg.conf.d section config file.

Currently I’m using a xorg.conf generated by nvidia-settings in one of my home machines, due to a dual-monitor setup.

After generating xorg.conf, the device sections are:

in xorg.conf:

Section "Device"
    Identifier     "Device0"
    Driver         "nvidia"
    VendorName     "NVIDIA Corporation"
    BoardName      "GeForce 7300 SE/7200 GS"
EndSection

in xorg.conf.d/50-device.conf

Section "Device"
  Identifier "Default Device"

  #lot of comments...

Option "UseCompositeWrapper" "True"

EndSection

My question is if the Option “UseCompositeWrapper” “True” will be used or not. In other words, if a section exist in xorg.conf then it’s correspondent in xorg.conf.d/ will be completely ignored or only the lines in xorg.conf.d/ that already exist in xorg.conf will be ignored?

Thank you.

My guess is that the section in xorg.conf.d/50-device.conf (including options) will be ignored … but it’s easy to find out.

If you put an Option statement without a Driver statement in xorg.conf as the sole config file, what do you think would happen? Even if it didn’t throw a specification error, you might get a default driver loaded which may not support the option statement. Unless they changed the specification rules (see xorg.conf man page), your orphaned Option statement should be invalid. In your scenario, why not just remove the ambiguity and put a Driver statement in the xorg.conf.d file? But then if it remains in xorg.conf, that should override.

Of course I could be wrong. :slight_smile:

Yes, of course (after you mentioned it ;)).

'Cos I’m too lazy…

Kidding :), I’m running a looong structural analysis in a VM which will take a few hours yet, so I don’t want to restart X now. while I was looking for something to do I stumbled into this option I added when I installed 11.3 - at the time it seemed to improve things, but they don’t seem to have worsened after I created the xorg.conf.

:slight_smile: It’s all theory, until you try it. Mind you, I spent some time once trying various driver options on a VIA graphics chip. With those that didn’t crash the system, I found it difficult to spot any real differences in performance. I expect with nvidia though, you can load them with heavier stuff so differences could be easier to measure.

On my system using 11.3 & nvidia the xorg.conf worked. YMMV.