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For LG OLED users: Mac mini M4 does not support HiDPI 4k over HDMI 2.1
- Thread starter dinosauradventure
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Thanks. I opened a ticket with Apple and referenced the OP's ticket number. Hopefully we'll get an update as to whether this can be patched.
Made an account to post on this thread.
I also just bought an M4 Mini base model.
I have an 8k Samsung TV and the Mini will output HiDPI @ 4k (8k signal shows on TV) but only at 30hz. In other words, 4k scaling with Mac mini m4 outputting an 8k resolution.
My TV should be able to accept a 60hz @ 8k signal. Currently unsure if the issue with only outputting 30hz is the Mac or my TV / HDMI 2.1 cable.
But my experience here is different to OP who I think is advising they are unable to get 4k scaling for an 8k native resolution.
I also just bought an M4 Mini base model.
I have an 8k Samsung TV and the Mini will output HiDPI @ 4k (8k signal shows on TV) but only at 30hz. In other words, 4k scaling with Mac mini m4 outputting an 8k resolution.
My TV should be able to accept a 60hz @ 8k signal. Currently unsure if the issue with only outputting 30hz is the Mac or my TV / HDMI 2.1 cable.
But my experience here is different to OP who I think is advising they are unable to get 4k scaling for an 8k native resolution.
Will the scaling work Fine on a Samsung 65inch 4K QLED TV with HDMI 2.1 Port and 120Hz Support?
Anyone tested out?
I really hope that there is no scaling issue. I havent received my Mac Mini yet….
Anyone tested out?
I really hope that there is no scaling issue. I havent received my Mac Mini yet….
You have a 4K TV, regardless if it's 32” or 150“. It applies across the board.Will the scaling work Fine on a Samsung 65inch 4K QLED TV with HDMI 2.1 Port and 120Hz Support?
Anyone tested out?
I really hope that there is no scaling issue. I havent received my Mac Mini yet….
Gist of this thread is: On a M4 Mac mini,
1. It’s either 4k 120hz or 1080p (2x scaling) 120hz. No in between scaling like 1.5x
2. Some people are also getting pixelated image on 4K 120hz
1. It’s either 4k 120hz or 1080p (2x scaling) 120hz. No in between scaling like 1.5x
2. Some people are also getting pixelated image on 4K 120hz
Reporting Here
Samsung 55” S95C with a high quality 8K cable via HDMI 2.1 does 144hz 1080p and 1440p but I can’t tell if it’s 10-bit how does once check this, Using a new M4 MacMini.
Samsung 55” S95C with a high quality 8K cable via HDMI 2.1 does 144hz 1080p and 1440p but I can’t tell if it’s 10-bit how does once check this, Using a new M4 MacMini.
Is this really true? I currently use M1 MacBook Air with LG C2 and I am using HiDPI 2304x1296 res at 60hz (max I can do with my cable).
Can Mac Mini M4 do 120hz HiDPI 2304x1296 with HDMI 2.1 cable on LG C2? I have M4 Mini in order but seriously reconsider if I am forced only to 1080p HiDPI.
In the context of this thread, or any time post-Apple Silicon, when discussing HiDPI in macOS we are referring to non-integer scaling that requires 2x the UI resolution is creating a virtual screen by macOS which then scales down to whatever the actual physical pixel output of the display is.
And with M4 and / or Sequoia 15.1, it seems the limit of how high res your UI can go has been changed or mistakenly imposed.
Yes, this is the issue. The text becomes jagged looking at 4K native with no scaling
WTF Apple. Why… just why. This better be a bug but if it is that raises the question, do they even bother to do proper QA 😮💨
I can’t believe we’re still dealing with BS like this FOUR years into the Apple Silicon transition 🤦♂️. Why do displays always have to be a pain point.
High res displays are not exotic anymore. FFS Apple basically pioneered / mainstreamed them more than a decade ago. This kind of thing needs to just work.
I can’t believe we’re still dealing with BS like this FOUR years into the Apple Silicon transition 🤦♂️. Why do displays always have to be a pain point.
High res displays are not exotic anymore. FFS Apple basically pioneered / mainstreamed them more than a decade ago. This kind of thing needs to just work.
Hi @Raspire,
it might be the cable or some other issue. The entry level M4 mini can output 8K@60Hz and the Samsung 8K lineup should work fine with it. I tried it on a Samsung 8K display (55" QN700C), everything looks great (3840x2160 HiDPI shows up fine). Make sure you have Input Signal Plus enabled for the HDMI connection, cable being high speed 8K@60Hz capable, device set to PC. Use 60Hz VRR for best results once the connection is fine.
This thread is about the issue of non-8K displays getting a 3072px (or with some ultrawides 3360px) HiDPI resolution limit. This limit is fine for those who simply use their mini in the living room or for most 4K monitor users (at 27" and 32" sizes 2560px-3072px HiDPI width is fine), but for some who wish to use their 4K TVs up close as monitors with supersampled HiDPI resolution to help a bit with font smoothing and/or have high quality accessibility zoom, this might feels limiting.
I think this limitation is there because of how the m4 mini supports different number of displays depending on the presence of at least one 8K display (with probably a non-8K display with a 8K scaled resolution counting as one) - because of this macOS tries to avoid needlessly giving a display 8K space so when additional displays are connected it does not have to do everything over again, disconnecting existing displays in the process. But this is just a theory, it might simply be a result of some simplification in how the logic works (trying to have a more universal logic that covers all the Apple Silicon lineup, with some exceptions for 8K and some ultrawide displays) which might be fixed later by Apple. The strange thing is that the system reports a 7680px or 3840px HiDPI horizontal GPU resolution limit (in the framebuffer port's `MaxSrcRectWidth` field - which was a reliable method to tell the limit for all prior Apple Silicon Macs), suggesting that the mini could do more.
This is entirely normal. It's simply rendering at the native resolution. Use a scaled resolution for more comfortable UI/text size. The 120% scale option ("looks like 3200x1800") is IMO about appropriate for the 48".
OP's usecase seems highly specific where they want to run their display at a HiDPI version of the native 4K resolution, so essentially at 8K downscaled to 4K. Maybe they have a TV that is larger than yours or they sit very close to it.
I used the LG CX 48" as a work display for a few years and felt I needed 1+ meter viewing distance for it to feel comfortable, and I still used it more like an ultrawide, putting my windows at the bottom 2/3 of the screen because I didn't have to look up.
It was not a good setup and I went back to a smaller 4K multimonitor setup, and now use a superultrawide version of that.
Is this just something Apple has decided arbitrarily? Or is this an ARM hardware limitation somehow? You'd think that the framebuffer could be any size, just increases GPU and RAM needed to render it.
It's just disappointing to find that even with TB5 DP 2.1 support, the M4 series is hampered by limitations like this, and only because Apple refuses to do anything about their scaling system to make it work better.
@waydabber
That’s a great reply, thank you very much.
As a side note: Iv also noticed that 8k AV1 decoding on YouTube fails to work and defaults back to 4k, this is in both the native 8k resolution (which is unusable because the text is tiny) and 4k HiDPI rendered at 8k.
That’s a great reply, thank you very much.
As a side note: Iv also noticed that 8k AV1 decoding on YouTube fails to work and defaults back to 4k, this is in both the native 8k resolution (which is unusable because the text is tiny) and 4k HiDPI rendered at 8k.
The buffer is on chip for Apple Silicon, so it was design to have a set pixel limit and cannot be increased after the fact. As per BetterDisplay, their notes says this:
"Maximum flexible scaling resolutions depend on GPU capabilities and the display's resolution (horizontal width limit is 6144 pixels for entry level Apple Silicon Macs, 7680 pixels for the Pro/Max/Ultra versions)."
This was for M1 to M3 gen, not yet updated for M4 and we are still trying to figure out. If there is no progression, at least there shouldn't be a regression.
Any modern "gaming" OLED monitor will provide indefinitely better colours after calibration than any modern Apple display.
And you'll get to enjoy 240 Hz refresh rate, with perfectly smooth animations, legible text during scrolling, and precise mouse movements.
Isnt this Workaround the current solution for the Scaling Issues at least for 4K Displays like TVs (3840 x 2160) with 120Hz over HDMI:
github.com
Or is this still not working as good as expected? 🧐
Fully scalable HiDPI desktop
Unlock your displays on your Mac! Flexible HiDPI scaling, XDR/HDR extra brightness, virtual screens, DDC control, extra dimming, PIP/streaming, EDID override and lots more! - waydabber/BetterDisplay
github.com
Or is this still not working as good as expected? 🧐
This was what we've been talking about and people already use this (all the way to the first post). It doesn't solve the problem. I recommend for you to go back re-read it.Isnt this Workaround the current solution for the Scaling Issues at least for 4K Displays like TVs (3840 x 2160) with 120Hz over HDMI:
Fully scalable HiDPI desktop
Unlock your displays on your Mac! Flexible HiDPI scaling, XDR/HDR extra brightness, virtual screens, DDC control, extra dimming, PIP/streaming, EDID override and lots more! - waydabber/BetterDisplay
Or is this still not working? 🧐
Do you notice a difference in sharpness between 3840x2160 and the resolution you mentioned? The first post also mentioned 3360x1890. Have you tried that?
I really hope that either Apple or BetterDisplay finds a Solution for this. Thats really sad for now 😭😭