Ubuntu 18.04.2 / nvidia-driver-430 / DP problem with 2 monitors


My configuration: Notebook AsusROG GL502VK, GTX 1070, Ubuntu 18.04.2, nvidia-driver-430, kernel 4.18.0-24-generic, Monitors DELL U2515H.

I have a problem with 2 monitors which are connected with a daisy chain DP. The configuration works great under Windows 10, but not in Ubuntu.

At each boot, even from the sleep state, the Nvidia X server settings show me that my 2nd monitor is disabled and enable the screen of the notebook which was previously off. One important point is that the monitor which is on is very often the first monitor, but sometimes it’s the second one.

To be able to use the 2 monitors, I had to do:

  • in Nvidia X server settings software, enable the second monitor, disable the internal screen of the notebook, and make my monitor as the primary one. But something after this, it’s the second monitor which is active, so it’s impossible to confirm the configuration, and the system goes back to the previous configuration and I have to retry it;
  • if I can confirm the configuration on the first monitor, the second one is in sleep mode. I had to do “xset dpms force off”, wait for the first monitor to go in sleep state, and after that move the mice, and that’s it. It works ! But it’s very complicated.

Do someone has an idea to solve this problem? I tried with other driver form nvidia: it’s the same with 415 and 418.

Thanks for help if you have an idea of the problem.