External Monitor works on prime-select nvidia but not on intel

I’m running a Lenovo ideapad laptop with AMD Ryzen 5 4600H processor + Nvidia GTX 1650Ti. I dual booted the system with Ubuntu 21.10 which uses the linux kernel 5.8.0-40-generic. I installed nvidia-drivers-460 from the additional drivers settings in Ubuntu. I also have a secondary monitor connected to the HDMI port.

My laptop works fine when set in prime-select nvidia, The monitor displays the screen, I am able to open nvidia-settings and modify the settings and also see nvidia-smi . But it consumes too much power. Therefore, I tried to switch to the integrated AMD renoir graphics card .

Once I run prime-select intel and restart the system, the second monitor is not being detected. I tried deleting /etc/X11/xorg.conf but it didn’t help. I also tried switching from gdm3 to lightdm but that also didn’t work.

Any way I could get he monitor working?

My xrandr output:

Screen 0: minimum 320 x 200, current 1920 x 1080, maximum 16384 x 16384
eDP connected primary 1920x1080+0+0 (normal left inverted right x axis y axis) 344mm x 193mm
   1920x1080     60.01*+
   1680x1050     60.01  
   1280x1024     60.01  
   1440x900      60.01  
   1280x800      60.01  
   1280x720      60.01  
   1024x768      60.01  
   800x600       60.01  
   640x480       60.01  

The external hdmi port is connected to the nvidia gpu, so if you turn it off, the external hdmi port is also off.

Hey @generix , thanks for the info. I was also suspecting the same thing. Is there any way I could verify it, other than the fact that the monitor is not working. Also, can I somehow get it working on the prime-select on-demand mode?

The xrandr only shows the internal display, so the AMD gpu doesn’t have any other outputs.
The on-demand mode is currently a work-in-progress with amd/nvidia combos, so this can’t really be used now.
Edit: better said, on demand+external output is a WIP, on demand by itself works.

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So, the only way for me to reduce the usage is the quality settings in nvidia-settings panel. I guess I can manage with that. Thank you @generix !!