i7 8650u - UHD 620 4k@30hz Video tearing with premium HDMI

[celenmeh]

Hello,

I have Dell Latitude 5490 with i7 8650U processor with an onboard UHD 620 unit.

I connect my laptop to 4k TV  with resolution 3180x2160 at 30hz.

When I watch 4k videos on Youtube or 4k movies with VLC, images are tearing and frames are sometimes slow, laggy. It is visible, especially in fast scenes.  

My Latitude has HDMI 1.4 port. 

If I switch to Full HD everything is so smooth and good. 

I am adding a video, you can see tearing lines. 

https://drive.google.com/file/d/1AhXE7x7nRZ-NANnXiQhdoW5f75hvAdqK/view?usp=sharing

[celenmeh · Accepted solution]

Ok...

I found out that it has nothing to do with any physical stuff.

I am running Debian 10 I needed to override my X11 configuration.

My system runs  /usr/share/X11/xorg.conf.d/10-amdgpu.conf, although I have intel chipset.

I set the configuration as below

Section "Module"
    Load "dri3"
EndSection

Section "Device"
    Identifier  "Intel Graphics"
    Driver      "intel"
    Option      "DRI"   "3"
EndSection

By the way, I noticed that tearing was actually happening for all videos. But I just notice that. I was playing some tearing tests and noticed even built-in output had that issue.