I posted in the DIY osciloscope PWM thread about dithering and how I've been able to make a cheap setup capable of recording it with an iphone SE on a tripod with a carson microflip microscope attached https://imgur.com/Pb27cPv. https://www.youtube.com/watch?v=vh0vRJNnHy8 (this was a p24h-10 monitor). All my monitor recordings were done on a g4560 using the hd610 igp in windows 10 with ditherig running.

An interesting thing I've found is that it seems you can't rely on panel bit depth specifications to know whether or not the display dithers. I recorded very clear dithering on my AOC u27v3 monitor that uses the PANDA LM270PF1L panel https://imgur.com/DW1FYjx. This panel should be true native 8-bit as it's also used in the AOC U2790VQ and Philips 276E8VJSB monitors, both of which are 10-bit (8-bit+FRC).

https://www.displayspecifications.com/en/model/f8d41b4a

https://www.displayspecifications.com/en/model/f02b1537

I guess this makes sense since the monitor's control board ultimately determines whether or not dithering is used. So slapping a budget control board that reaches 8-bit color by using 6-bit+FRC onto a native 8-bit panel will just make the 8-bit panel dither. Now the real question is do the control boards that reach 10-bit through 8-bit+FRC also use 6-bit+FRC to cover the initial 8-bit color range?

    chahahc

    I posted in the DIY osciloscope PWM thread

    Move to a new thread for organizational reasons. All posts preserved and a redirect link is in the other thread.

      machala Yeah i think this plays a part in the eye strain especially since theres a difference in general image quality from switching from a K4200 to a A4000. I can try writing there but i doubt they will take it seriously unless enough people join in and complain.

      HAL9000 The exact revision is "GA104-875-A1" and it seems closest to the RTX 3070 TI(GA104-400-A1) and the RTX 3070 TI 16GB which never was actually released, I wonder if all GA104 based GPU's will cause the same symptoms or if moving up to a GA102(RTX 3080, 3090, A5000) based GPU would be any better. It was reported here that a RTX 3090 gave @screengazer eyestrain so it seems like maybe the GA102 series will cause the same symptoms. https://ledstrain.org/d/1048-new-graphics-card-rtx-3090-gives-eyestrain

      https://www.techpowerup.com/gpu-specs/nvidia-ga104.g964

      https://www.techpowerup.com/gpu-specs/nvidia-ga102.g930

      It sounds like you have similar experience with your 3060 Ti as im having with my A4000, i tried raising the sharpness in the control panel and it helped a very small about amount but still not usable for me.

      I have a RTX 4000 based on the TU104 GPU arriving soon which comes with Samsung VRAM, i really hope it will be free of eyestrain. If that fails ill try a RTX 5000 after that and see what happens. The 5700 XT's ive tried have been the worst so far though.

      https://www.techpowerup.com/gpu-specs/nvidia-tu104.g854

          6 days later

          So i received my Quadro RTX 4000, and out of the box, this card is certainly usable, the image quality is "different" its not bad/worse, just different, but it feels its still slightly less flat, it doesnt cause me eyestrain/dizzyness and im glad to be able to finally use a somewhat recent GPU.

          I saw several posts about a program called NvColorControl

          https://ledstrain.org/d/1048-new-graphics-card-rtx-3090-gives-eyestrain/5

          https://ledstrain.org/d/1119-g-sync-laptop-zero-eye-strain-from-gaming-tons-from-regular-use-help/20

          https://www.avsforum.com/threads/2020-lg-cx%E2%80%93gx-dedicated-gaming-thread-consoles-and-pc.3138274/page-21#post-59699820

          I ran it with the settings "NvColorControl.exe 10 RGB 2" and the image looks the same as my Quadro K4200 now. From what i understand about reading the instructions from Vinz80 is that setting "2" is disabling the state for Nvidia to enable the dithering, if thats true then that would mean Nvidia is just enabling dithering for everything even if the monitor has a true 10bit panel.

          I still need to test it under Windows 10 to see if NvColorControl helps, but on my Windows 7 installation it made a huge difference.

            6 days later

            Jack Thanks for your report! This is a great find. What driver version are you using on your Windows 7 setup?

              Jack So how do you guys figure out if the given card has Samsung RAM? It's not specified anywhere and even if you have the card in your hand all the internal components are covered by the cooling setup, so you don't see it unless you take the heatsink off…?

                @degen For Windows 7 the last officially released Quadro driver is 441.66 but i used the oldest stable branch version i could find which is R410 U6 (412.29) February 22, 2019. They also have an older one from the "New Feature Branch" R415 U2 (416.78) November 13 2018. My Windows 7 installation is from an ISO without SP1 and i install the SP1 and minimal related updates manually and replace the outdated security certificates with one from a Windows 10 install by exporting each one manually since on an old Windows 7 ISO they will be expired. I never use Windows update to make sure nothing unwanted gets by.

                @machala Usually they are listed in GPUZ, and im pretty sure all of the Quadro RTX and RTX A series use only Samsung VRAM and not Micron, Elpida or Hynix. If it isnt listed in GPUZ then you would have to take apart the heatsink/fan assembly to inspect the VRAM modules, which gives an opportunity to replace the thermal paste since the stock thermal paste from the factory is usually bad.

                  Side note, my IGP only says DDR3 because it's using system memory. CPU-Z can be used to show you who the manufacturer is on the SPD tab--in my case, Kingston.

                  Jack Hi, I am getting "NVAPI NvAPI_Disp_ColorControl: NVAPI_ERROR" with NvColorControl.exe, are you getting the same. Anybody knows what the issue might be?

                      machala I never received that error, what version of Windows are you running and what graphics card and driver version?

                          Jack It's Windows 10 21H2, NVidia drivers 457 DCH, the ones WIN 10 installed by default. I tried on a Gigabyte 1050 Ti D5, will be trying this on my second card MSI 1660 Super Ventus today. Unfortunately tomorrow is the last day when I can return the cards and the way I see it is that I'll have to do it.

                          • Jack replied to this.

                              machala Try installing the non DCH version of the drivers and see if that fixes it.

                                  machala I always got that error whenever I tried NVColorControl some years back. I never found a solution.

                                    Jack 472.84 standard driver, no change… perhaps it works or some cards only…

                                    EDIT: same with the 1660 SUPER…

                                      Jack

                                      I may have missed reading something but are you saying you got two identical A4000 cards, but one of them has samsung memory and is OK to use but the other does not have samsung memory and is not ok?

                                      OR

                                      Do they have different GPU chips?

                                          HAL9000 RTX 4000 is not RTX A4000

                                          I've seen similar theories about people having "good" cards with "brand A" of VRAM and "bad" cards with "brand B" and other than that I've seen absolutely no BIOS dumps between any two such cards. Particularly in the case of the 900 series where there are discrete examples of of "good" and "bad" cards that are otherwise the exact same card. I theorize a BIOS transplant could convert a "bad" card into a "good" card.

                                              JTL I believe it. Years ago I had a retail Radeon that I used with a CRT monitor. I did play with bioses for it, and even back in those days I actually replaced the retail bios with a third party oem bios because I felt the picture looked better on the CRT with it.

                                              • JTL replied to this.

                                                  HAL9000 No the RTX A4000 is the newer Ampere based card similar to a RTX 3070 with Samsung VRAM which is unusable for me. The card i can use is the previous generation Quadro RTX 4000 Turing based card which also has Samsung VRAM. I wish that was the case though since if i had two identical A4000's i would 100% flash the bios of the good copy to the unusable copy.

                                                  Has anyone else had success here with an RTX Turing based 20xx GPU? One user Jimbo66 reported success using a MSI RTX 2070 Super Ventus https://ledstrain.org/d/717-amd-gpu-s/5 His experience with the 5700 XT also mirrors the symptoms i had when i tested that card.

                                                  In regards to Ampere based GPU's its seems so far no one has reported any success stories and they cause a lot of symptoms.

                                                    Sunspark Going to laugh so hard if the underlying mechanism with the "good" versus "bad" cards that are otherwise the same model ends up being the same situation.

                                                      9 days later

                                                      Jack

                                                      I ran it with the settings "NvColorControl.exe 10 RGB 2" and the image looks the same as my Quadro K4200 now.

                                                      1) can you say that the fonts become more thin and sharper after this action?

                                                      2) does it create a registry branch:
                                                      [HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\services\nvlddmkm\DisplayDatabase\XXX_mon]
                                                      with the variable:
                                                      "DitherRegistryKey"=hex:db,nn,nn... ??

                                                      3) You only need to run the NvColorControl.exe once or every time you restart/login for the desired effect(image looks the same as my Quadro K4200) ?

                                                      4) Does this setting go off after actions like changing resolutions, starting games, sleeping?

                                                      5) Does your monitor support 10 bit color ?

                                                      I still need to test it under Windows 10 to see if NvColorControl helps, but on my Windows 7 installation it made a huge difference.

                                                      6) As far as I know, the Quadro series drivers have a built-in options in the driver GUI interface, which allows you to enable and disable dithering without additional programs.

                                                      Do you see this GUI switch?

                                                      It is possible that the default GUI dithering switch value of K4200 is different from A4000 ?

                                                        dev