photon78s Interesting discussion here. This link just for learning about VCOM:

You mean this patterns are not vcom? Okay, its better to name it "vcom mechanism" or Interlace pattern artifacts which used in pcmonitors reviews

I measured today aoc 24b1h, dexp df24n3, Xiaomi Mi Desktop Monitor 1С. All of them have 2-step pixel twinkling ( left - right ).

Acer 240y dont have this, its vcom similar to my benq ( 4-step pixel twinkling, twice low frequency compared to new monitors ). I got acer for testing

      simplex

      Nope. No assumptions of anything. Just trying to figure this concept out. I some point maybe you could add vcom to this forum's wiki or the glossary section. Btw, is your username "simplex" refering to simplex noise?

          simplex from the word simple - simpler, simplification of the complex

          ok I will add after done some tests. I found 2 main vcom patterns - horizontal ( left to right ) and chess pattern

              simplex

              Nice. I see some usernames alluding to engineering terms or concepts from computer programming. Maybe some "monitor engineers" are lurking here in the shadows…

                  photon78s

                  Here is some results I got:

                  When I set my 165hz xiaomi panel up to 45hz ( 30…45 ), no green vcom columns anymore and you can use monitor and feel only grapfic card + windows dithering, no "dithering" added by monitor

                  https://cloud.mail.ru/public/frSj/jFbYfBr1w

                  When I set to 46hz or more (50, 60, 100, 120, 165) - vcom add its bars and eye-nerve got strain after 20+ minutes

                  https://cloud.mail.ru/public/WjBP/ga9DxqJGa

                  p.s. all vids slowed down 4 times. There is static image recorded

                  p.p.s. all modern monitors I tested have same vertical bars or another pixel sticking protection. I think pair-based vcom (first frame: left green pixel shine and right is closed, second frame: left is closed and right is shine) overload eye-nerve. My old-safe benq dont have pair vcom, it have 4-step

                  In engineer menu I found no options regarding vcom adjustments. I think it controlled with extra chip in panel board scheme, or it is t-con config

                      simplex

                      Will this vcom still be an issue even if you remove the backlight such as when doing a conversion of a regular display panel to a solar backlit display?

                          photon78s

                          I think yes, the backlight is typical - big blue peak similar to my benq, but red peak is KSF-based. Without vcom you can relax more than with vcom ( setting 120hz+ framerate )

                            a month later

                            My new findings:

                            1. If you have a severe attack ( you feel eye-strain even using safe displays for a week ), Glycerin and Ethylmethylhydroxypyridine will help reduce eye pressure. Consult a neurologist first
                            2. There could be " tail " condition ( your nerve still tensed even when irritant has gone )
                            3. GPU make some records in motherboard's nvram, so its better to clear it out ( remove motherboard CMOS battery for 30 min ) after bad GPU usage
                            4. to completly remove nvidia drivers configs, use DDU ( sometimes you can replace GPU but eye-strain can still exist due to "previos card rendering configuration" stored in windows )
                            5. software also matters, I stick with win10 1809 17763.1098 with updates blocked, my current nvidia driver is 536.23 ( check "make clean installation" when install, after that check you using 8bpc / RGB / "full colorrange" in nv control panel, it disable dithering )
                            6. using CRU you can delete monitor colordata to let windows use "default" colorspace without tranformation ( same effect which people get using HDMI-DVI or HDMI-DP cableconnectors, or switchers )
                            7. using monitor profiles or windows night mode (yellow tint shift) also activate color transformation
                            8. If steps above doesnt help, you need to replace hardware and test again. My working top comfort is z390 ( lga1151v2 ) + rtx2070s ( TU104 based ) + benq ( a month ago I bought a new benq 2420z and a used z390 + 9600kf = everything is great on 2nd PC )

                              qb74 There is a "safe" gudeline I'd say for monitors.

                              Not really. Just out of your guide, flicker has zero impact on me whatsoever, and refresh rate ABOVE 60hz causes me symptoms, higher resolutions are worse for me, and I need to be sub 3000k color temp, not 5000k

                              I know there is a strong desire to find a "silver bullet" that cures us, but it doesn't exist. Each person needs to find a specific setup that works for them and then never change it.

                              • qb74 replied to this.

                                  ensete

                                  flicker has zero impact on me whatsoever,

                                  Flicker impacts every single human being, whether they perceive it or not. All studies I've come across point to this conclusion.

                                  and refresh rate ABOVE 60hz causes me symptoms,

                                  You might've chosen monitors which have a modern wide color gamut backlight (KSF or QDEF), every monitor is a story of it's own.

                                  higher resolutions are worse for me,

                                  Same story as above, depends on panels which you've used.

                                  and I need to be sub 3000k color temp, not 5000k

                                  Yes, ideally no blue light is best but not everyone can afford using a red screen all the time.

                                  but it doesn't exist.

                                  It does, people here just seem to like going on wild goose chases.

                                    Wonder how ksf phosphor interacts with the chromostereopsis effect. Probably doesn't help the eyes focus.

                                    simplex Speaking of which running windows update services significantly affects eye pain, unexpectedly ).Even if you installed a clean Windows, but left the update services on, then on average after a day will arrive “hidden updates” which will not even be in the list of updates and you will feel pain in the eyes, experienced on myself. Just some information for "club" members ).
                                    Then, how I am struggling with "previos card rendering configuration" or a hidden Windows update. Step by step:
                                    1) I uninstall the driver in the normal way for Windows.
                                    2) I reboot into safe mode and uninstall via DDU.
                                    3) I go back to normal mode and check that the services and tasks to update widnows are stopped.
                                    4) By sequentially running the following commands:
                                    DISM.exe /Online /Cleanup-image /Restorehealth
                                    sfc /scannow
                                    5) Installing a different driver than the one I had.
                                    6) Reboot
                                    7) Repeat steps 1, 2, 3, 4.
                                    8) Install the driver you need (in my case, the one I had).
                                    9) Reboot


                                        23 days later

                                        After 1 week being without any screens except smartphone, eyes got rested

                                        When I sit in my z390+rtx2070s, pain between brows begins after 2 hours. I switched GPU to gtx1060, cleared CMOS removing battery, and pain stopped

                                        So, after switching from gtx1060 to rtx2070s, 1.5 years is time when I started to feel strain. Same time exp for my wife but with rtx3080ti card

                                        Looking GPU specs, I found gtx1060 and 1660s (which is safe according to this forum) are directX 12.1, when rtx20 and newer gen are directX 12.2 ultimate. Intel UHD630 or UHD770 or IRIS XE or Intel Arc iGPU - also 12.1, when amd 610m and newer are 12.2

                                        My question: who use dx12.2 gen graphic card without any issues? Note, dx12.2 support was introduced in win10 2004 and newer. In my theory, win10 <2004 and dx12.1 graphic cars are safest combos

                                        qb74 do you have an example of this fast oscilloscope with light probe? And/or guides on how to make it and how to test the flickering with it?

                                        • qb74 replied to this.

                                            qb74 it's very interesting! Don't you find the Opple Light Master device acceptable for those measurements? It's cheaper and can detect hi-frequency light changes

                                            • qb74 replied to this.
                                                4 days later

                                                Ivan_P
                                                Until I see a disassembly of it, along with a specsheet of it (since it's basically emulating a oscilloscope + light probe setup, characteristics such as bandwidth of probe and device itself, shape of frequency response etc.), I don't consider it a valid option for comparisons.

                                                Ideally, one would disassemble panels and probe the backlight itself for brightness fluctuations, but this is not possible for most.

                                                  dev