Mac mini display problem

jalucky13

I recently got a mini 2022 M2 and hooked it up to my hp monitor. I have had this monitor for a while and have used it with a dell optiplex 7070 micro and used linux and windows 11 with no issues. The strange thing is the mac mini hooked up to it causes weird dizziness eye strain issues where the dell doesn't hooked to the same monitor

I thought it was the monitor that made the difference in eye strain?

jordan

jalucky13 might want to try a anker displaylink hub. not sure if it will fix it but it handles video output differently

AshX

jalucky13

Are you using Stillcolor to disable GPU dithering? You may have to use BetterDisplay to adjust scaling as well. Make sure Font Smoothing and the usual culprits are also disabled. What OS version are you on?

Donux

jalucky13 Sounds like consistent symthom. I had the same experience with macbook air m2. Nothing really solved it. Tried changing bit output, RGB to Ycbrc output, still color, font smoothing etc. Since TCON is not in play when external monitor is used, there must be something GPU related. I would not intuitivelly accredit that to superficial visual configuration causes, due to severity of a strain. It was more likely some sort of micro-flicker or temporal dithering. But we need to continuosly test test test. Especially on possible manipulation of all available GPU parameters that could be controlled by software.

jalucky13

jordan My monitor is VGA so for the mac im using usb-c to vga adapter from apple.

jalucky13

AshX Im using stillcolor but i didn't know about Betterdisplay

AshX

jalucky13

BetterDisplay allows you to disable dither by monitor output. Stillcolor should disable all outputs by design.

We need you to be very specific about your monitor specs and the Mac Mini. What version of MacOS is the M2 Mini running and what is the size and specs of your monitor.

MacOS has serious scaling issues on non-Apple monitors if they don’t have certain resolutions at different sizes (i.e. 5K at 27”, 6k at 32”). BetrerDisplay allows you to apply different resolutions to somewhat rectify this.

Also you have to disable Font Smoothing. All the new Macs out of the box have it on and it makes text incredibly blurry and can cause dizziness. Make sure you’ve disabled Auto Brightness, True Tone, and Night Shift as those won’t play well on non-Apple screens and can introduce dithering.

Donux

I noticed this with the M4 MBA on multiple monitors I tested at Micro Center. I can’t be 100% sure they were FRC free, but I did notice the gray color flicker on several. Stillcolor did change the shade of gray on one of them from gray to brown, so it was having an effect. My theory was that the laptops are still sending a blend of the feed from the internal screen to the external monitor, or certain cables somehow trigger MacOS to apply dithering (ColorSync processing, maybe?).

The Mini has no TCON so in theory Stillcolor should be able to send a clean 8-bit signal. The other possibility is that MacOS Sonoma and Sequoia are applying dithering differently than Monterey and Ventura either using a different mechanism from the GPU or processing from ColorSync. Perhaps ColorSync kicks in on certain external monitors of lower quality or based on the cable used to attempt to make the limited color gamut look better.

Clokwork

Is the monitor capable of handling HDR or 10 bit color? Or is it a native 8 bit only supporting 8 bit color?

jalucky13

Clokwork I have no idea its a HP V223

Clokwork

jalucky13 It seems from my findings, that monitor is 6bit+FRC. You may want to seek a native 8 bit panel that only supports 8 bit color.

Donux

AshX Interesting you mention cable, wouldn't usb-c simply send data output in its rawest format possible ? Also, some folks mentioned about HDMI being a better soliution to them, so maybe older formats have some processing layer which is smoothing things out.

jalucky13

AshX its running the newest os update

AshX

Donux

USB-C and/or Thunderbolt would be the highest fidelity for Macs in theory. OP is using a USB-C to VGA adapter from Apple so we can infer it is an older monitor.

Two schools of thought:

A. We can “force” lower bit using lower bandwidth cables which will result in the receiving signal being unable to dither.

B. MacOS will compensate on a lower fidelity monitor by applying more dither via GPU or ColorSync to make MacOS look “better.”

Given OP is on the latest version of MacOS, I think it’s more likely this is an inherent issue with Sequoia, which people have complained about

jalucky13

Others who had a comfortable M2 machine who updated to MacOS Sequoia 15.4.1 (I believe that’s the latest?) complained of similar symptoms. I would try to see if you can revert to an older version of MacOS, perhaps Sonoma, and see if that resolves your issues. The M2 can go as far back as Monterey. I don’t know if you may have to try to revert firmware, too. Others on this forum have more experience with this sort of thing.

If you don’t want to do that, you can try a different monitor. I assume since you’re using VGA your monitor doesn’t have an HDMI input.

JTL

AshX We can “force” lower bit using lower bandwidth cables which will result in the receiving signal being unable to dither.

I don't know about Macs, but I believe other devices have used dithering to compensate for a lower bandwidth connection between the GPU and display.

Donux

AshX I have never ever tried HDMI with apple silicons. Just did not bother buying all adapters. But who knows, it might have been a saving solution. Soon I will have my hands on Zenscreen, so will see if this is a game changer as some have claimed. One thing I know is that noMachine remote connection is better, but kind of feels strainy. Maybe it is learned neurological reflex or something, or just poorly rendered blurry fronts using remote connection.

AshX

JTL

I’m curious if anyone has or is interested in testing this with a Mac. I’d be inclined to think MacOS wants to push 10-bit exclusively at all times since Big Sur/M1.

This is one of the big debates, right? Will MacOS still dither on a true 10-bit external display?

Another question I’d love to know the answer to is whether MacBooks are incorporating the processing done on the internal display into the signal that is being sent to an external display? And if so, in theory, the Mac Mini wouldn’t do that.

Stillcolor/BetterDisplay has proven it can fix the actual visible flickering and glitching that was present on a ton of Dell monitors during the M1 era. People used Stillcolor and it fixed the problem. So clearly that was a clashing of Apple’s dithering algorithm with true 8-bit sRGB capabilities or the monitor’s own FRC algorithm.

Interestingly, Apple did provide an update that worked for some users and not others. Even more interesting is that Stillcolor worked for almost all of those users, but a subset found it stopped working after a time and they had to reboot. These are folks not with our issues.

Seems to me those are clues as to what is going on. I think you and others here have established certain programs like Photoshop, Premiere Pro, Safari, Photos, etc. apply their own form of dithering and they will switch on even with Stillcolor enabled.

If all this is true and not imagined, then it’s not much of a stretch to assume ColorSync or different connections can engage dithering even if Stillcolor is disabling it.