Help: eye pain from Thinkpad P14s

[Diretissima]

I have a new Thinkpad P14s (AMD) with non touch IPS panel for a few weeks now and I cant stand the screen. After using it for a very short time my eyes hurt and I get headache. The eye pain is very distinct and directrly behing the eyes. It didnt show right away but after a week of using it, wich was at the same time I started playing Tombraider 2013. I later found out this game is known to cause eye problems. I did some tweaks but no luck.

The screen seems to have no PWM (according to notebookcheck, and tested with camera). I use a warmer color profile and set the brightness to an appropriate setting. I checked for temporal dithering with a 10x magnifier and could not make anything out. I see multiple lines at testufo/line test.

OS is Ubuntu and I installed AMD drivers. After reading here in the forums the room was probably darker than it should be.

I can work on other monitors and my older Thinkpad for hours and have no problems.
What can I do? Any settings, drivers or softeware, or even change the OS? What are the chances that I cannot use this Laptop at all and have to get rid of it?