I am having the same exact issue as described in [this support thread](https://us.community.samsung.com/t5/Qled-and-Frame/Q90T-Screen-Tearing-with-Game-Mode-On-at-1440p/m-...) but on another model, the Q80T 49".
In the case in the link, the problem was solved by changing the refresh rate, but I have the 49" version with no 120hz option.
My graphics card is an RTX 2060 hooked over HDMI to the 4K TV with maximum refresh rate of 60hz. Have tried different resolutions, been testing and switching different HDMI cables and tried different power sockets. The problem only occurs when using game mode.
The line at the bottom of the screen is continually delayed from the rest of the screen whenever my PC is using the TV as display with Game Mode on. It’s not random flickering like "normal" screen-tearing. The problem can be seen on the link below.
[Video of the screen tearing](https://1drv.ms/v/s!Ag02o9o548YDg819Sl2tnBDCv2Ydbw)
The same problem has been described, using DEX on other models [here](https://eu.community.samsung.com/t5/tv/regression-bug-samsung-2020-qled-tvs-gamemode-is-breaking-the...) and [here.](https://eu.community.samsung.com/t5/mobile-apps-services/samsung-dex-paired-with-samsung-qled-2020-t...)
Hope someone can help
I'm having the same issue too. Only way I am able to play anything in 1440p is to set games to play in borderless window mode and have desktop resolution set to 1440. I have the 43 inch frame tv. No issues at 1080p or 4k.
Exact same issue here on the TU8000 43" over HDMI @1440p in game mode (60 / 59 hz). (Canadian version)
Is this a faulty set? I am thinking of returning it.
Thank you for any help,