Issues with Lenovo Legion 740 laptop. Connection Speed from GPU to monitor runs at 2 lanes DP instead of 4

Operating Systems & Open Source Linux
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Alright. I’ve been having issues with this the past five or so hours.

I installed Linux Mint 21.2 on my girlfriend’s computer, as she had to get more storage and then the Windows 10 license stopped working after changing the SSD. No worries, she was fine with trying out Linux, as she’d seen me use it.

Everything worked fine out of the box, except for issues with the built in fractional scaling. Easily fixed by just using 100% scale and then upping the font size.

The issue now is that when the laptop is under heavy stress (sometimes when it’s just idling) White lines appear for a fraction of a second.

Apparently this is caused by the driver wanting to use 2 DP lanes @ 8.10 Gbps instead of 4 DP lanes @ 5.40 Gbps.

[Link redacted]

According to this forum post, it works in nvidia 450. I tried getting that installed, without luck. It’s not supported anymore. I tried using the nvidia-dkms-450-server package instead, that installed and worked. The white lines were gone! The issue is that Steam refused to open, and pretty much every OpenGL/Vulkan application. I saw in the nvidia-settings that it did now run at 4 lanes instead of 2.

I also tried switching from Discrete graphics to Switchable graphics, as a few posts online said it made a difference with other Lenovo laptops. This just made Linux Mint not show anything. CTRL+ALT+F1 gives me a text-prompt as usual, but CTRL+ALT+F7 is just black with a little dash in the top left corner.

Does anyone of you know how to force Linux to use 4 lanes instead of 2? Or how to install nvidia-450 on a modern Linux distro? Or how to switch to Switchable graphics?

(Sorry for the new account, I couldn’t access my old one that only had a few posts anyway)

Thank you for your replies.

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Well… I managed to get Switchable graphics to work!

I just did mv /etc/X11/xorg.conf /home/user/xorg.conf.bak and the black screen is no more!

I’ll test more in case there’s still flickering.

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  • Steps forward and puts head on the block * Welcome to LEVELONETECHS. I’m thinking the reason your post has had so many views and very little (if no) response might be due to the subject material at hand. Lenovo has had their butt dragged into court a couple of times already and have been convicted of providing embedded fishing ware in their PCs. This is one piece of hardware I would only be too happy to dispose of. Lenovo is not a good name. Personally, I’d just junk the thing. Strip out your RAM and your drive and be done with it. There are plenty of used laptops you can get these days for a song. Sorry to break it to you and I’m sure some reader will get all up in arms over my reply. I’m too old to care. This can be Googled.

Wishing you the best

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It seems that running the GPU through the integrated graphics worked wonders!

“Nvidia On-Demand” mode works wonders and Steam seems to always pick the dedicated RTX 2070. For everything else Cinnamon has added a “Run with dedicated GPU” button on.
The computer is finally not hotter than the surface of the sun all the time!

Only issue I have encountered is that the Borderlands games seem to freeze the whole computer if running in “On-Demand” mode instead of “Performance”. But running the game with gamescope seems to fix this.

I hope if someone else spends five hours searching the Internet for answers to this, they can see this forum post.