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  • Random Find: Use this KVM significantly helped with Win 10 symptoms

Could be a lot of things.. if it's an active adapter then the video signal is processed from one format to another, like displayport to hdmi, etc. They don't all use the same chip. And while I don't have a KVM I am using an adapter.. my PC has DP and HDMI outputs, but I'm using an DP to HDMI adapter because the HDMI output on the PC doesn't look as nice. It was the same thing with the Dock I have for my deck.. the HDMI output from the dock's converter wasn't as good as a DP to DVI adapter I got.. so, the switch probably just has a chip or something that doesn't suck.

Another could be the video timings.. there's the timing that is stuffed into the monitor EDID, and there are other timings for the same resolution but use slightly different values.. switch might use timings from its own tables instead of just copying what the monitor or OS provided. I know timings does make a difference because I spent awhile in Linux manually entering timings and comparing them.

4 days later

I wish someone can test for dithering with and without the adapter

async I find that YCbCr mode shows most evident gradient banding when dithering is switched off. RGB, at least on my monitor, does almost nothing when dithering is switched off, maybe some minor artefacts appear and that is it.

    You will see the banding without the use of ditherig as well. Not sure if this is a compression artifact, or a dithering thing.

      Sunspark Well smooth transition of grey color to my understanding means that screen generates more grey tone variations, which also would mean more dithering. So seeing banding is a good thing, as it implies at least there is no aggressive temporal dithering. Spatial is kind of tricky one.

        Sunspark

        When Intel drivers are set to spatial dithering on a 6-bit panel (NOT temporal!), and you scroll down on a page, even a "still" spatial dithering pattern can cause photos to slightly flicker as you scroll.

        This is because the image "interweaves" with different parts of the pattern as the image moves downwards, causing the pattern to appear like it's alternating back and forth, even though the pattern itself "technically" doesn't change.

        On most e-ink screens like BOOX, it's even "worse" as the pattern itself regenerates in a very obvious way whenever there is movement, even though it's still when there's no motion. (This might be a solvable problem in the future, as I've heard the Modos open source e-ink monitor project implemented a different dithering method that tries to keep the pattern still…)

        However, there's an interesting situation (especially if the display is a TN) where I've observed the "checkerboard pattern" created by spatial dithering at times having the side effect of "accidentally increasing LCD polarity pixel inversion flicker" in that area -- depending on the pattern -- as the checkerboard sometimes lines up with the same kinds of conditions that cause LCD inversion to be visible.

        This kind of "accidental pixel inversion" means a spatial dithering pattern can occasionally still increase flicker(!) even if the pattern is not supposed to "intentionally" be changing!

        Finally, Intel's version of spatial dithering sometimes decides to slightly alter the hue of a pixel to increase precision further even on grayscale content (the reason why they do this is that adding a slight color can "perceptually affect brightness" in a more fine-grained way). This is distracting to me because sometimes different gray shades in a UI can subtly look reddish or bluish when they're all supposed to "just be gray".

        If the panel is good, I agree that spatial dithering is generally fine in most cases and it doesn't cause that much of an issue (especially compared to temporal) but there are still reasons to disable it.

        In my case, I prefer disabling it because I have my screen set to grayscale often and I get distracted by the subtle color tints on certain shades of gray.

        The flickering while scrolling as a photo interweaves with the pattern also definitely becomes noticeable enough at times to become annoying (especially when I'm scrolling very slowly)

          ocean10 how is it working for you? mine changes things for the better if not 100% better.

              reaganry

              That's awesome to hear it's working so well for you.

              I have a follow up next week for all the light therapy things I've been working on. Once that is done I plan to try it. I've got the Windows 10 version that Microsoft will support until 2032 on my work computer (10 year old Lenovo T450s) so I've been surviving with that in the meantime.

              Does it work for you on Windows 11 or Windows 10? I'd love to be able to use a Windows 11 machine.

              What wires/connectors are you using?

                  3 months later

                  ocean10 I was actually looking at this thread wondering the exact same thing because I'm in a similar position. I've purchased this KVM and when it arrives, I'll test it with Windows 11 with an Intel A750 and maybe some other GPUs 👍️

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