AgentX20 Ive spoken with some people from the local hacking and tech community and they explained to me that it makes sense. The analog nature of VGA really washes and smoothes out any harsh dithering flicker.
But as we know - not always and not all the same. I guess it depends on input.

Ok so I tried connecting my windows 7 laptop, which never gave me eyestrain through VGA, with a displayport->DVI adapter and bam eye strain and nausea.
This is incredible....I don't know if it's my monitor (Benq GL2250HM) but I can't use it with anything other than VGA.

    uizz The adapters are not all the same. Different chips in them and the microcode to run them will produce different output. I have several adapters here and there are subtle differences here and there.

    My NUC has a DP output and a HDMI output, but what most people don't know is that on newer machines the HDMI output is actually an internal DP-to-HDMI adapter.. so in my opinion it's generally better to just use a chosen adapter for DP to whatever. Older machines had native HDMI output or native VGA output.

    There will be DP-to-HDMI 2.1 adapters this year. Worth trying then. 2.0's are out but might as well wait since you have a working VGA solution.

    The only time the VGA solution does not work well for me on my hardware is with protected streaming video. On Amazon, for TV shows it doesn't care and will give you full resolution on VGA on 7, but for movies it cares a whole lot and will lower the resolution/bitrate. On Netflix it cares for both shows and movies and in addition, requires windows 10 to get full bitrate (this means even if you are using HDMI on 7, Netflix will limit your resolution and bitrate). Because of this (and also because my monitor is on an arm now and my vga cable was 1.5 feet or something) I started using the HDMI port on the monitor for now.

    It may not be your monitor, it may just be a poor quality adapter, but there is one additional thing you can try.. there is a possibility your monitor is using a different chip internally for the DVI port than it is for the HDMI port, so in that case, what you could do is get a DVI-to-HDMI cable and try the HDMI port with your existing DVI adapter. It will work because the DVI and HDMI video signals are 100% compatible. You won't be able to use all the HDMI options with a DVI adapter on the HDMI port but the video will be there. A cable with a DVI connector at one end and HDMI on the other is cheap because it's just a cable, no chips.

    Incidentally, I have an old HDMI to VGA adapter cable that strips HDCP (intentionally). I tested it out and it does work to stream movies over VGA, but the problem is that specific adapter is locked into limited range and I have no way to change it to full range since it's set in the internal hardware. I would have to use a color calibrator to compensate for the range change but I don't have a calibrator. It's another option to consider of course.

    9 days later

    What about using 2 adapters: hdmi>Vga vga>hdmi?

    9 months later

    I had never looked at HDMI vs VGA cables as potential triggers. Now something puzzling happened. All of a sudden I got awful long-lasting symptoms, such as eyestrain, neck tension, blurry vision and headache, after shortly looking at the monitor of a shared computer that did not use to give me trouble. I checked all the settings and nothing was changed. Finally I figured out that the HDMI cable was replaced from this type to this other type. Looking at the specs of one and the other as a non-expert, the only difference I spot is that the new cable is supposedly of higher quality and "4K".

    Has anyone experienced surge of symptoms by changing the HDMI cable? I could test a bunch of the new versus the old and see if it is systematic or just a one-off bad cable. I wonder because I read a review in which the author says that there is no reason to buy expensive HDMI cables as they make no difference whatsoever.

    Thanks in advance for any insight!

      AGI

      The fancy cable will have a higher data transfer rate, conversely the cheaper cable will have a lower transfer rate. Not sure what the visual implications are of running a low spec cable though, I had assumed it just wouldn't work, but I wonder if your monitor was running at a lower framerate or resolution or something?

      • AGI replied to this.

        HDMI cables are not active converters. They're just a cable carrying a digital signal. Skeptical that this cable means anything, however simply put the old one back in as a test, it will work for hdmi 2.0 too.. the specification requires both the display and the device to support the 2.0 protocol and the old cable you listed was already listed as supporting 4k, deep color, etc. It will work just fine with 2.0.

        • AGI replied to this.

          Seagull

          Thanks. No, the monitor is running with the same settings.

          Sunspark

          The old cable definitely works. It was not replaced because defective or non suitable. A few devices were added to the working station that now holds six monitors and all the cables were replaced with fancier ones not for a specific reason. I will try to do some more tests. I was inquiring because I never expected a difference going swapping HDMI cable. In fact, I already tested a few HDMI cables of the old type and none of them causes eyestrain. Thanks.

            AGI

            I don't understand why that would be the case though. It's carrying a digital signal. All the cables should be completely interchangeable if they display a picture.

            • AGI likes this.
            a month later

            I had the chance to restore the old HDMI cable and use the old setup for four weeks, while no one was around. After some adjustment due to the hostile environment (very bright yellow-blue LED overhead lamps, which could illuminate a football field, in the line-of-sight of the display), I could reach the end of the day with minor discomfort. Definitely, no memory effects once leaving the room.

            Then, things turned to the worst. The upgrade of the working station resumed and was completed, including plugging in the new fancy HDMI cable. I immediately felt my neck and shoulders tensing, and eyestrain developing. I insisted and after 2-3 days I would exit the room devastated at the end of the day, like, I once went to a movie theatre at night and I had to leave. I could not watch the movie. I described my symptoms more in details in the thread dedicated to using the eye patch, since I did try to use the eye patch to alleviate my symptoms. Coupled with little sleep, using the eye patch turned out to be suicidal.

            Back to the display and what I perceive, the problem seems to be that the white background glows inhomogeneously with the new HDMI cable. I am not sure if flickering is the right term, but it is like I can see all the white pixels glowing distinctly, and this affects either my eyes or my brain. I decided to not avoid the problem and to carry through. The situation has not worsened luckily. After a week, the level of discomfort seems to have come slightly down from its peak and have plateaued. However, it is still bad and I am not confident it will ever get to an acceptable level. My daily life is still badly affected. Besides the eye and neck and shoulder pain, I feel really tired and deprived of energy at the end of the day.

            I am not an hardware expert and I trust what you guys wrote regarding HDMI cables. Yet, my symptoms are real. They go away if I put the old HDMI cable back, and they return if I use the new cable. Now, can it simply be a bad cable?

              AGI I am not an hardware expert and I trust what you guys wrote regarding HDMI cables. Yet, my symptoms are real. They go away if I put the old HDMI cable back, and they return if I use the new cable. Now, can it simply be a bad cable?

              Wouldn't be impossible

                AGI Go to one of your coworkers computers, one that doesn't sit next to you and swap the HDMI cables. It's the same cable, nobody will notice it was exchanged. See if the switch helps you. If they don't like it, let them be the one to do the complaining for a change.

                10 days later

                JTL

                This is definitely possible. See this video: https://www.youtube.com/watch?v=r04DYZ1-BXE

                I used to have a bad quality HDMI cable that caused the monitor very much flickered (so much that it was clearly visible to every person). Flickering was much smaller during pressing HDMI plug into the monitor. So in this case probably the plug was defective.

                  a year later

                  matix yes, bad HDMI cable might create bit errors, and those can create noise similar to the video you've sent.

                  but i don't see how they can create flicker.

                  dev