I have a double monitor setup. One of my monitor, an ASUS VG249Q1R can run at 165 Hz after I enable overclocking in its user interface. Before, it can only run 60 Hz. But when I set it to 165 Hz it only shows random colors (white, blue, green, ...). It works with 144 Hz though.

This is my /etc/X11/10-monitor.conf with 144 Hz that works:

Section "ServerFlags" Option "BlankTime" "0" EndSection Section "Monitor" Identifier "HDMI-A-1" Modeline "192x108" 220.75 1920 2064 2264 2608 1080 1083 1088 1130 -hsync +vsync Option "PreferredMode" "192x108" Option "RightOf" "DisplayPort-0" EndSection # This is the monitor Section "Monitor" Identifier "DisplayPort-0" Modeline "192x108" 452.50 1920 2088 2296 2672 1080 1083 1088 1177 -hsync +vsync Option "PreferredMode" "192x108" Option "Primary" "true" EndSection 

And this is the same file with something with 165 Hz that causes X or whatever to show those random colors:

Section "ServerFlags" Option "BlankTime" "0" EndSection Section "Monitor" Identifier "HDMI-A-1" Modeline "192x108" 525.00 1920 2088 2296 2672 1080 1083 1088 1192 -hsync +vsync Option "PreferredMode" "192x108" Option "RightOf" "DisplayPort-0" EndSection # This is the monitor Section "Monitor" Identifier "DisplayPort-0" Modeline "192x108" 455.75 1920 2088 2296 2672 1080 1083 1088 1177 -hsync +vsync Option "PreferredMode" "192x108" Option "Primary" "true" EndSection 

Both modelines are calculated using cvt.And finally, this is my /etc/X11/20-amdgpu.conf (I use an AMD Radeon RX 590):

Section "Device" Identifier "AMD" Driver "amdgpu" Option "TearFree" "true" Option "VariableRefresh" "true" EndSection 

What can I do in order to have a refresh rate of 165 Hz instead of 144 Hz?