Originally Posted by AaronP
Adding modes through RandR is not supported yet, but you should still be able to add them through xorg.conf. The driver still provides a lot of detail about where various modes come from if you start X with the -logverbose 6 option or turn on the ModeDebug option. Check /var/log/Xorg.0.log to see where your unwanted modes are coming from, and then you should be able to use the various ModeValidation options to turn off implicit modes, such as NoXServerModes, NoVesaModes, NoPredefinedModes, and NoEdidModes.
Thank you for the reply. That makes sense if its not yet supported.
The idea is I want 2 different refresh rates for each head, which I can do just fine through xorg.conf, except RANDR then also advertises these 2 specific modes for both my monitors, which I do not want, I need to force each monitor to a specific refresh.
Minecraft for example somehow sets the mode via RANDR which causes my secondary monitor to get set to the same refresh rate as my first monitor. If I was able to remove the incorrect refresh rate from the secondary monitor in the RANDR list that would be okay, but its not possible.
It would be possible if we were able to set custom modes through RANDR as then we can force specific modelines to a specific screen and no longer use xorg.conf to set specific modes, or of course the other option is to disable RANDR entirely until this is supported. (Games can no longer change the modes, which is good as I don't run stuff in fullscreen anyhow)
Hope that explains it well.