Screen flicker while using MUX laptop in dgpu mode

Issues & Assistance
1

So I have a lenovo legion y740, with an i7-9750h and a 2070 max-q. My laptop has a MUX switch that lets me switch between

1. Dedicated GPU mode (laptop runs only on the nvidia card for better performance, Intel igpu is turned off )

2. Hybrid mode (igpu + dgpu is turned on, helps in saving battery life) Now With proprietary drivers installed. I have no problem running on hybrid mode, everything works fine But when I go to my bios and turn on dgpu mode, arch boots, but the second GPU wokload is even slightly strained (like say a 1080p60 video) the screen starts flickering heavily. Even without strain flickering is less frequent but still happens.

I had a look at Hybrid graphics - ArchWiki And only the first part of the page offers any info about laptop that HAVE a MUX switch. I looked at how to solve screen flicker by forcing full composition pipeline and that did nothing: tps://wiki.archlinux.org/title/NVIDIA/Troubleshooting#Avoid_screen_tearing

I also looked at changing DRM modset, and only changed it in the config file ( I didn't do the latter half) and that too did nothing, but I wasn't sure if following through with it fully would solve screen tear, and honestly also wasn't 100℅ sure how to go about it: NVIDIA - ArchWiki … de_setting If anybody could please shed some light on the above, telling me what i did wrong and what I should do, and links to related posts too would be much appreciated!

2

I think that your mistake was that you did not study the laptop User Manual very closely.
I find hard to believe that

When both cards work should consume more power.
I thought everyone knew that vendors build their HW with MS-Win in mind.

Your situation, translated to Linux, looks like you are switching computers HW on and off. This is new to Linux (automation mechanisms).

Since your system works well on the Hybrid mode, what is the real reason you want to use the dGPU-only mode?

4 Likes
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Also cross posting across multiple forums is poor form...

6 Likes
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So I can close here, thank you @elloquin