My config:

MB: Gigabyte GA-B150N Phoenix-WIFI
CPU: i7-7700
RAM: 16GB RAM 2666MHz
GPU: ASUS GeForce GTX 1660 SUPER STRIX ADVANCED 6GB
SSDs: Samsung M.2 128GB + Crucial MX500 500GB
OS: Windows 10 Home

CorvusCorax Meantime, if anyone has some other suggestion, please write here. I will be grateful.

Just consider yourself lucky that you know that your hardware is usable for you. It's much harder when there are more variables - all you need to do is get back to your working software setup and then be conscious that from now on, upgrading anything in your setup should not be taken lightly.

@si_edgey OK. Still it's very strange for me that the problem appears right now. I spent many hours using different PCs with different configuration (I'm IT guy) and never had any issues of this type :/

Hi Peter,

Just to confirm, everything is fine when you stop using the new monitor? so the problem appears to just be the monitor?

If that is the case, I would suspect LCD inversion to be a potential cause of your problem. You might read about it here http://www.techmind.org/lcd/

In short, an LCD pixel's voltage has to invert every frame to prevent degradation. This creates a flickering effect. All LCD panels will do this, even if they are marketed as flicker free. The way inversion is implemented and perceived will vary between monitors and LCD technologies. However, a 240hz monitor will flicker through inversion at 4x the frequency of a 60hz monitor. My suspicion is that this higher frequency flicker is giving you a migraine.

Temporal dithering is another potential cause, your GPU will alter its output every frame even if displaying a static image to improve colour quality. Similarly to inversion, using a 240hz monitor will dither 4x faster than a 60hz, potentially making migraines more likely.

If possible, setting your 240hz monitor to a 60hz setting will resolve any problems caused by faster dithering. It might solve the inversion problem, but I am not sure if setting it to a lower framerate will actually change how inversion is implemented - it may continue inverting at 240hz regardless of the framerate you set it to.

Further assuming you have a migraine, it may take you several days to feel 100% again.

Just chiming in as I had the exact same problem with a Dell monitor. S2716DG Rev. A09. Reading this thread turned me on to the fact that it could be pixel inversion or, coil whine. But yeah... I feel ya. It sits in the corner collecting dust now, which is too bad, because it was a great gaming monitor.

I found something interesting about Covid-19 and headaches and light sensitivity. Check this out:
https://www.theraspecs.com/blog/covid-19-coronavirus-headaches-light-sensitivity/

FYI
In my workplace almost every person was going through Covid19 or something similiar. The only person who wasn't sick was me. Maybe my symptoms are the result of having light version of C19? Because it was so strange that my problem occured from day to day. Like something trigger that.

Of course it is only hypothesis, I will investigate other solutions in near time. For now my eyes have to rest.

    CorvusCorax

    After recovering from Covid I had visual problems, mostly unrelated to screen tolerance. It did worsen my screen tolerance noticeably, making me more prone to migraines from LCDs. However, I had noticed this trend prior to contracting Covid, but the infection may have accelerated it. I was very sick with Covid for 6 weeks.

      Seagull Wow! Really sorry to hear this.. that thing isn't a joke.. hope you will make a full recovery.

        Sunspark JTL

        Its quite unpleasant for sure! I'm very interested in what the research on the long term effects will be. After covid I found I had the following new problems: terrible anxiety (fortunately fading), joint pain (might be getting better but hard to tell), visual distortions (which got a lot worse after consuming hallucinogens), and a reduced tolerance to LCDs (but as I say that was getting worse before covid), and fatigue (fortinately relieved with caffeine and sugar).

        Based on these symptoms, the best explanation I can come up with is that covid has triggered an autoimmune reaction. Where my immune system is attacking is serotonin receptors, receptor 5ht-2a best fits the symptoms. It is associated with migraines, visual distortions, and joint pain.

        Getting back on topic

        CorvusCorax

        I've increasingly found that my food allergies are worsening my tolerance to LCDs. Not saying that's causing your problem, but I am saying you might need to think outside the box. If you can't find any help with the suggestions already made, it might be worth keeping a log of your screen tolerance to see if there is any fluctuations. If there is, logging your daily activities might yield some correlation.

        Lauda89
        I'm from italy too! Is there any way to keep in contact? I dont know how to send a private message 😕

          Sofista90 You can click on the "chat" bottom on the top and there you can send a private message. Or you can add me on telegram "Andrea Laudani @Evilxardas"! Ciao 🙂

          14 days later

          Hi again, just wanna to inform you that I rolled back 2004 update to 1909. I also installed older nVidia drivers. Nothing's changed. There is last option - rearrangement my room to previous state (I changed some things like I put UPS under the desk, near my feet and some minor changes of monitor placement). If that doesn't help I will give up. This will mean that my body has stopped dealing with this monitor or that it is a symptom of a disease. No idea.

            CorvusCorax In my experience IT can take over a week for the symptoms to dissipate, so perhaps give it a bit of time if you're absolutely sure you're back to the old setup and drivers. There's also a stress element - in the same way that a person allergic to pollen may develop a reaction when you produce a bunch of plastic flowers, I'm certain that our bodies can trigger headaches and migraines when working on machines that have caused you problems in the past. But it does fade with time, for me at least.

            6 days later

            I discovered (with an AM radio) that the switching power supplies in my UPS and monitor bricks and desk speakers were giving off serious radio frequency interference. i switched to headphones & moved things away (to another circuit) with extension cords. not a complete fix, but definitely makes a difference.

            25 days later

            CorvusCorax Any updates on your situation? We are on the same boat and I'm a Pole as well, so if you found any helpful specialist in Poland, please let me know.

              Dominic For now I'm back to my old monitor (Dell 2209WA), it's OK. Not great, but better. I think my problem comes from few things. Which one trigger the symptoms IDK, but I'm sure that is linked to my neck. For now I try to exercise the spine and my neck. I see some differences for better. I will let you know if something change. If you are from Poland you can write PM to me.

                7 days later

                CorvusCorax I feel you so much man. I also thought it was neck, or eyes, or whatever. You have to consider that all these are constants, you are used to this kind of posture/habits. But buying a new monitor and immediately getting strained, well this changes the whole equation here, it's obvious. Happened to me with S2721DGF, got nauseating migraine, which ended up making me photophobic and phonophobic... Couldn't look at any light source for 3 days straight. You should know you are not crazy, it' just something we haven't discovered yet. It's there I'm sure about that. The pixel inversion thing is interesting idea, but I got terrible inversion on my screen (BENQ GL2460), and have 6bit + FRC always on. Also got 60hz with terrible ghosting, yet, I feel just fine, can sit on this monitor for 8 hours straight. I don't know... maybe it's the brain that is used to this shitty monitor, and it's hard to adapt to something better...

                Hi Guys, i've tried 4 new monitors and i had problems with all of them. However, I can work with my old syncmaster 12 hours without any problem. I know some people improve their sight changing drivers, room light, etc but I have the suspicion that the problem it's the new monitor hard.

                Try running them on 1080p instead of 1440p. For some reason that has resolved eyestrain on several high DPI monitors, to run that at lower than native res, notable my BenQ EW3270U and EW3280U.. And it's much better than just increasing scaling. I think there's more to it than "things are bigger". Some shenanigans get disabled on some monitors when run at lower than native.

                  dev