I've had headache and migraine problems for a few years when using my work PC. I suspected the monitor at first and bought 4 different of them. I tried LED, LCD, Anti flickering and even a 500$ Monitor 240hz and all that stuff.
I noted that my plasma TV gave me no trouble for over 7 years. I also use an imac 2014 mostly plugged via HDMI on my TV and i have no problem at all. On day, I decided to plug my PC on the TV and the headaches were back in minutes. So i figured it was something with the PC.
I have an RTX2060 and as I understand it doesn't use Dithering, so I don't think dithering is the problem here. I tried disabling the GPU and still no relief. I can really feel the headaches in minutes as I switch from imac/TV to Desktop/TV setup.
I also tried blue filtering glasses + Flu.x. It seemed to work for a moment but the headaches came back quickly after a few days.
Also my phone Samsung s8 is not giving me headache as long as the desktop doesn't trigger it Then, the s8 is killing me
I read a lot of users had the opposite problem, where the imac was the issue. Maybe together we can find the problem.
Any clue what is happening with my head ? Also, I never had eye strain and I still don't. Only headaches that turns into migraine if I don't stop as soon as it starts.