Something that may be important: in my /etc/X11/xorg.conf file, I have: Section "Screen" Identifier "Screen0" Device "Device0" Monitor "Monitor0" DefaultDepth 24 Option "Stereo" "0" Option "metamodes" "DP-3: nvidia-auto-select +0+0, DP-4: nvidia-auto-select +0+0" Option "SLI" "Off" Option "MultiGPU" "Off" Option "BaseMosaic" "off" SubSection "Display" Depth 24 EndSubSection EndSection
and in the /var/log/Xorg.0.log file: [ 23.807] (II) NVIDIA(0): Validated MetaModes: [ 23.807] (II) NVIDIA(0): "DP-3:nvidia-auto-select+0+0,DP-4:nvidia-auto-select+0+0" [ 23.807] (II) NVIDIA(0): Virtual screen size determined to be 3840 x 2160 [ 23.811] (--) NVIDIA(0): DPI set to (232, 240); computed from "UseEdidDpi" X config [ 23.811] (--) NVIDIA(0): option [ 23.811] (II) NVIDIA: Using 6144.00 MB of virtual memory for indirect memory [ 23.811] (II) NVIDIA: access. [ 23.843] (II) NVIDIA(0): Setting mode "DP-3:nvidia-auto-select+0+0,DP-4:nvidia-auto-select+0+0" This is what selects the mirror mode for the two monitors. -- Vincent Lefèvre <vinc...@vinc17.net> - Web: <https://www.vinc17.net/> 100% accessible validated (X)HTML - Blog: <https://www.vinc17.net/blog/> Work: CR INRIA - computer arithmetic / AriC project (LIP, ENS-Lyon)