This is a common issue with laptops, for two monitors you usually have to use the discrete GPU and not the inbuilt GPU which is typically used for power saving not performance.
One thing to try first though is to set up the monitors with xrandr (this is just an example, change options to suit your set up);
Hi, I’m facing the same problem:
01:00.0 VGA compatible controller: NVIDIA Corporation TU117M (rev a1)
05:00.0 VGA compatible controller: Advanced Micro Devices, Inc. [AMD/ATI] Renoir (rev c6)
After installing nvidia-drivers the hdmi monitor disappeared. I’ve spent many hours to make both external monitor and laptop display to work, but no way. The only shitty workaround I found is to use them alternatively.
To use hdmi monitor with nvidia create a new conf:
If I’ll have more time to find a better solution, I will share it here.
The only reason I need nvidia-drivers is Mate presents some flickering and artifacts on the hdmi monitor in the default installation. KDE works just fine, why? Shouldn’t be Mate lighter and more resilient?
The problem here is that a dual GPU device has an inbuilt low power device that will display on the built in display, and as soon as you want to use the HDMI port to drive an external display, you are connected ONLY to the discreet GPU that is used for higher output (frame rates, graphics intensity), and the issue is that these two outputs are not connected internally at all.
With some config, you can run only the discrete card (Nvidia) and use this to drive both displays;
After a fresh install, both laptop display and hdmi monitor are working fine, with amdgpu and nouveau drivers, in all possible combination of primary/extended. But with Mate I have flickering and artifacts on the hdmi monitor. The issue arrives after installing native nvidia drivers and blacklist nouveau.
I have tried Driver “modesetting” suggested in your link, but no fortune for me, hdmi not detected, just eDP.
I have also tried without success a long list of suggestions of GPT-4o and DeepSeek. For now AI is more artificial then intelligent, just accumulative knowledge, without a fully understanding of the problem.
