5K2K at 120Hz with Mac Mini M4

[Riot Nrrrd]

Now where's the person with the M3 Ultra Mac Studio to show us the same test? 🤔

I was about to buy an M3 (Pro or Max) MacBook Pro to avoid this whole shebang but then I found out that the M4 based MacBook Pros have a superior 'quantum dot' display (in addition to having the nano texture screen option that M3 based MacBook Pros don't have), so now I'm even more frustrated than I already was ...

 

[ClassicMartini]

Now where's the person with the M3 Ultra Mac Studio to show us the same test? 🤔

I was about to buy an M3 (Pro or Max) MacBook Pro to avoid this whole shebang but then I found out that the M4 based MacBook Pros have a superior 'quantum dot' display (in addition to having the nano texture screen option that M3 based MacBook Pros don't have), so now I'm even more frustrated than I already was ...

The - current - HiDPI limit of 3360 x 1418 isn't so bad - on a single monitor.

Take Chrome/Safari for example. You just "punch-in" to, say, 110%, 120% until you get an ideal scale for you. And its super crispy - real HiDPI - text.

Apple's (current) HiDPI limit becomes really annoying when you have multiple monitors of different sizes and resolutions.

The 110% Chrome scaling becomes 125% or 90% (visually) as you drag from monitor to monitor, using Apple's presets. I have tuned my 3 odd-ball monitors* with Better Display to appear consistent as one drags a window from one screen to another.

For my set-up, think I'll have to get the Dell U4025QW, as the primary - right in front of face - monitor for the extra crispy real 3840 x 1620 hiDPI, and then 'equalise' the relative resolution, as discussed above, of the monitors surrounding it with Better Display


*
1 x 45" 5120 x 1440. (on top)
1 x 40" 5120 x 2160 (in front)
1 x 34" 3440 x 1440 (to right)

Display info export for Waydabber attached.

 

[Riot Nrrrd]

For my set-up, think I'll have to get the Dell U4025QW, as the primary - right in front of face - monitor for the extra crispy real 3840 x 1620 HiDPI

In my particular case, my 34” LG barely fits on the desk, so I don’t think that Dell would fit. Plus, I really dislike curved monitors.

 

[maksakal]

In my particular case, my 34” LG barely fits on the desk, so I don’t think that Dell would fit. Plus, I really dislike curved monitors.

Besides just being larger, Dell 40" 5k2k also has lower sharpness (139 PPI) than 34"(163 PPI). I also use LG 34" 5k2k which is the sharpest ultrawide available on the market. I wish there were never models but not yet

 

[JimbB]

Just picked up an M4 MacBook Air, and stumbling onto this fun limitation. For reference I'm paired to a Samsung C49RG9x. These are my options:

 

[kasakka]

The Studio Display having the 5120 actual pixel width is similar enough to the 5k2k displays, in that, if I am not wrong, all the Pro/Max/Ultra chips of the M1/2/3 generation can output up to 3360 HiDPI width with macOS settings, 3840 HiDPI width if unlocked by like BetterDisplay.

My photo / screenshot of the demo M4 Max Mac Studio just shows and confirms it behaves just the same as the M4 Max MBP, the highest HiDPI being 3200 means it is still capped or bugged, or whatever is happening.

The issue afaik is that the max limit for a scaled resolution is a 7680x7680 frame buffer. You tend to hit the horizontal limit most often. Note that there is no reason why the GPU shouldn't be able to render eg 16K and scale that down to whatever is needed. This is just a limit that Apple has imposed on either hardware or software for some reason.

MacOS HiDPI scaling works by "target res * 2" scaling.

Apple's own 5K and 6K displays both just skirt under that 8K framebuffer limit for the scaling options they offer. On the Pro Display XDR, 6016x3384 at 120% scaling would result in a 10027x5680 render resolution. At 150% scale it would be 8021x4512. Both are above that 8K framebuffer limit. So unsurprisingly the 6K display just goes straight from native 6016x3384 res -> 3008x1692 HiDPI, which results in a render res of 6016x3384.

M4 Max or Ultra won't make any difference. We will likely have to wait until Apple either:

- Lifts the limitation in MacOS or hardware.
- Refactors their entire scaling system to something less naive so it works more like how Windows does it where the capabilities of the display, connection etc are not a factor in the scaling levels offered.

 

[Chancha]

The issue afaik is that the max limit for a scaled resolution is a 7680x7680 frame buffer. You tend to hit the horizontal limit most often. Note that there is no reason why the GPU shouldn't be able to render eg 16K and scale that down to whatever is needed. This is just a limit that Apple has imposed on either hardware or software for some reason.

MacOS HiDPI scaling works by "target res * 2" scaling.

Apple's own 5K and 6K displays both just skirt under that 8K framebuffer limit for the scaling options they offer. On the Pro Display XDR, 6016x3384 at 120% scaling would result in a 10027x5680 render resolution. At 150% scale it would be 8021x4512. Both are above that 8K framebuffer limit. So unsurprisingly the 6K display just goes straight from native 6016x3384 res -> 3008x1692 HiDPI, which results in a render res of 6016x3384.

M4 Max or Ultra won't make any difference. We will likely have to wait until Apple either:

- Lifts the limitation in MacOS or hardware.
- Refactors their entire scaling system to something less naive so it works more like how Windows does it where the capabilities of the display, connection etc are not a factor in the scaling levels offered.

We know that 7680 buffer width limit.
And that the M1/M2/M3 Pro/Max/Ultra could hit that, at least with BetterDisplay (3840 width HiDPI)

And then, the poster on the previous page who "Took a bullet for the team", confirmed that the M4 Max Mac Studio *cannot* do this, stuck at 3360 width, on top of the 20 pages of discussion prior confirming the same on the MBP and minis. (except when connected to that one Dell display)

This I believe is the core of the discussion of the thread, the entire M4 generation kind of refuses to even match what the M1 to M3 gen could do in terms of HiDPI screen width.

 

[kong0329]

The issue afaik is that the max limit for a scaled resolution is a 7680x7680 frame buffer. You tend to hit the horizontal limit most often. Note that there is no reason why the GPU shouldn't be able to render eg 16K and scale that down to whatever is needed. This is just a limit that Apple has imposed on either hardware or software for some reason.

MacOS HiDPI scaling works by "target res * 2" scaling.

Apple's own 5K and 6K displays both just skirt under that 8K framebuffer limit for the scaling options they offer. On the Pro Display XDR, 6016x3384 at 120% scaling would result in a 10027x5680 render resolution. At 150% scale it would be 8021x4512. Both are above that 8K framebuffer limit. So unsurprisingly the 6K display just goes straight from native 6016x3384 res -> 3008x1692 HiDPI, which results in a render res of 6016x3384.

M4 Max or Ultra won't make any difference. We will likely have to wait until Apple either:

- Lifts the limitation in MacOS or hardware.
- Refactors their entire scaling system to something less naive so it works more like how Windows does it where the capabilities of the display, connection etc are not a factor in the scaling levels offered.

That is not the point of this discussion.

The point is M4 pro/max, and even the baseline M4 has enough frame buffer to support 3840 hidpi, but it turns out only one product can do 3840 hidpi, Dell U4025QW.
This is probably a software bug because we know that at least one product works, but Apple is just doing what Apple does and fails to fix it for months.

 

[davewolfs]

Someone really needs to make a sticky post summarizing 22 pages of complaining.

I bet the Ultra works just fine just because it’s not an M4 😂

 

[Riot Nrrrd]

Another one of my dumb questions …

If 3840x1620 HiDPI is the “ideal”/default scaled resolution for Ultrawide 5K2K displays, then is the equivalent “ideal” on a current Apple Studio Display 3840x2160 HiDPI? 🤔 (And, if so, I assume it’s not available on M4-based Macs.)

On a different note, can the whole M4/HiDPI problem be avoided by buying a 6K display like the Apple Pro Display XDR (that I can’t afford) or the Dell 6K U3224KB (that is butt ugly)? C’mon LG and ASUS already!

 

[Chancha]

Another one of my dumb questions …

If 3840x1620 HiDPI is the “ideal”/default scaled resolution for Ultrawide 5K2K displays, then is the equivalent “ideal” on a current Apple Studio Display 3840x2160 HiDPI? 🤔 (And, if so, I assume it’s not available on M4-based Macs.)

On a different note, can the whole M4/HiDPI problem be avoided by buying a 6K display like the Apple Pro Display XDR (that I can’t afford) or the Dell 6K U3224KB (that is butt ugly)? C’mon LG and ASUS already!

3840x1620 UI on a 40" 21:9 is ~104 PPI (UI res)
the default 1:2 UI res of a 5k ASD, the 2560x1440 UI on a 27" 16:9 is ~112 PPI (UI res)
in other words, wanting 3840x1620 on a 40" 5k2k is simply trying to simulate the default Apple UI size.

Can't comment on 6k on M4s, I don't remember anyone trying this on the XDR and reported back. The only place that 3840 HiDPI is guaranteed to work is on 8k displays.

 

[Riot Nrrrd]

3840x1620 UI on a 40" 21:9 is ~104 PPI (UI res)

Well in my case I have a 34” LG 5K2K so the PPI would be higher …

Why would the default UI resolution on an ASD be 1:2 when on the 5K2K Ultrawides it is 3:4? 🤷‍♂️

 

[kasakka]

Another one of my dumb questions …

If 3840x1620 HiDPI is the “ideal”/default scaled resolution for Ultrawide 5K2K displays, then is the equivalent “ideal” on a current Apple Studio Display 3840x2160 HiDPI? 🤔 (And, if so, I assume it’s not available on M4-based Macs.)

On a different note, can the whole M4/HiDPI problem be avoided by buying a 6K display like the Apple Pro Display XDR (that I can’t afford) or the Dell 6K U3224KB (that is butt ugly)? C’mon LG and ASUS already!

"Looks like 3840x1620" is just a good text/UI size for a 40" 5120x2160 display. Personal preference might mean you would prefer slightly higher.

Same deal with the 27" 5120x2880 Studio Display. The "looks like 2560x1440" integer scaled is fine, but I liked the one step up from that for the extra desktop space. I don't think I'd go any higher for the size. If it was 32" size, then things would be different.

The issue is entirely about what people would prefer to have for a good text/UI size that is not too big or too small, and Apple not able to provide options for some displays because of their scaling limitations.

Whether buying a 6K is a solution depends on if you like the integer scaled option, considering you won't have any way to go higher than that.

 

[Chancha]

Well in my case I have a 34” LG 5K2K so the PPI would be higher …

Why would the default UI resolution on an ASD be 1:2 when on the 5K2K Ultrawides it is 3:4? 🤷‍♂️

The thing is, you asked "ideal", which itself is subjective, but in trying to answer the question I chose one metric that makes sense, which is if you want to maintain the same physical real world size for the UI elements, there I used the ASD default as a reference.

3840x1620 on a 40" 21:9 would give you roughly the same UI size as a 2560x1440 on a 27" 16:9 (ASD/5k iMac).
Notice the actual resolution of the panels are not even in the equation. Therefore the scaling factor is irrelevant at least for now.

Whether or not when displaying this UI "resolution" would look sharp (so need to go higher), or if it is even possible, are the follow up questions. At this point you may begin inspecting if the scaling factor is giving you issues under macOS, or if it will even work. Which brings us to the point of this thread: 3840x1620 UI refuses to work.

 

[ClassicMartini]

We know that 7680 buffer width limit.
And that the M1/M2/M3 Pro/Max/Ultra could hit that, at least with BetterDisplay (3840 width HiDPI)

And then, the poster on the previous page who "Took a bullet for the team", confirmed that the M4 Max Mac Studio *cannot* do this, stuck at 3360 width,.

Still bleeding

Honestly, as most of my 'work' is in Chrome, I've learnt to live with it (Shh, don't tell Apple). By adjusting the zoom level in Chrome using command + or minus - 110% sweet spot, for my eyes - , and fiddling around with the desktop UI via System Settings to get a goldilocks zone of crispy legibility, without looking cartoonishly large.

 

[Riot Nrrrd]

The thing is, you asked "ideal", which itself is subjective, but in trying to answer the question I chose one metric that makes sense, which is if you want to maintain the same physical real world size for the UI elements, there I used the ASD default as a reference.

3840x1620 on a 40" 21:9 would give you roughly the same UI size as a 2560x1440 on a 27" 16:9 (ASD/5k iMac).
Notice the actual resolution of the panels are not even in the equation. Therefore the scaling factor is irrelevant at least for now.

Whether or not when displaying this UI "resolution" would look sharp (so need to go higher), or if it is even possible, are the follow up questions. At this point you may begin inspecting if the scaling factor is giving you issues under macOS, or if it will even work. Which brings us to the point of this thread: 3840x1620 UI refuses to work.

When I said “ideal” I meant as in, the OS seemed to default to 3840x1620 scaled HiDPI, so I assumed the OS thought that was an ideal default resolution to pick on Ultrawide displays.

Again, I’m on a 34” LG not a 40” Dell so that UI comparison wouldn’t be the same for me, I don’t think.

You’re also mentioning 2560x1440 HiDPI again without explaining why you’re using 1:2 scaling. I’m not understanding why if 3:4 is the default on a 5K2K display, then why wouldn’t you use 3:4 (i.e. 3840x2160 HiDPI) on the Studio Display.

In my own particular circumstance, I have a 5K2K display so this M4 restriction of disabling 3840x1620 HiDPI is hitting me right where it hurts. If I can get native 5120x2160 res from an M4-based Mac that will be way too tiny for my Senior Citizen eyes. On the other hand I’m used to 2560x1600 on a 30” screen so obviously I don’t really want to go any lower than that, the whole point for me in buying the LG 34” originally was to get more screen real estate than what I already had.

 

[Ishimura]

I am actually being very much put off buying a Mac Mini and getting into the Mac side of things because of how difficult it is to find a good quality 4k monitor that isn't hideously expensive.

Ideally it would have 120hz too, but I'm being realistic. It's crazy how difficult it is to find a monitor for budget or a midrange price. And then threads about this problem are full of people suggesting that you buy a £1000+ monitor - the base M4 Mac Mini costs £599!

 

[Chancha]

When I said “ideal” I meant as in, the OS seemed to default to 3840x1620 scaled HiDPI, so I assumed the OS thought that was an ideal default resolution to pick on Ultrawide displays.

Again, I’m on a 34” LG not a 40” Dell so that UI comparison wouldn’t be the same for me, I don’t think.

You’re also mentioning 2560x1440 HiDPI again without explaining why you’re using 1:2 scaling. I’m not understanding why if 3:4 is the default on a 5K2K display, then why wouldn’t you use 3:4 (i.e. 3840x2160 HiDPI) on the Studio Display.

In my own particular circumstance, I have a 5K2K display so this M4 restriction of disabling 3840x1620 HiDPI is hitting me right where it hurts. If I can get native 5120x2160 res from an M4-based Mac that will be way too tiny for my Senior Citizen eyes. On the other hand I’m used to 2560x1600 on a 30” screen so obviously I don’t really want to go any lower than that, the whole point for me in buying the LG 34” originally was to get more screen real estate than what I already had.

I brought up the ASD default was only meant to use Apple as a reference, we can assume they know what they are doing while designing and choosing their displays. We can disregard the scaling in that part of discussion, again I mentioned 1:2 was only trying to point out that's what Apple decided to build the whole display logic on. We can go back a bit pre-retina, the LED Cinema Display was also a 27" 2560x1440, as with many 27" displays of the same era, even now (but more with gaming displays). So a 2560x1440 at 27" must be deemed somewhat a comfortable UI size, back when HiDPI was not yet a thing.

Then with the default UI scaling that macOS choses for the ultrawides, well I can only guess, these are 3rd party and not the 16:9/16:10 norm, it is hard to pinpoint what contrived logic Apple used to determine which UI scaling is the default when seeing one. Like you found out, it is not about the pixel scaling, otherwise they would just default every other displays into 1:2 doubling, where most will have UI comically large.

Again I was only trying to show my own line of thinking in prioritizing "UI real life size" when talk about an "ideal". Whether or not the native res of the panel can allow a good scaling with good sharpness against that ideal UI size, is what comes afterwards.

 

[Riot Nrrrd]

@Chancha Appreciate the clarification. Thanks.

 

[Beau Slim]

I am actually being very much put off buying a Mac Mini and getting into the Mac side of things because of how difficult it is to find a good quality 4k monitor that isn't hideously expensive.

I wouldn't let this thread deter you from getting a "normal" (16:9) 4K monitor and using it with an M4 mini. A 27", in particular, will look fine to most people even if they work with text all day.

 

[davewolfs]

Still not fixed in latest update. Unreal.

 

[Riot Nrrrd]

Still not fixed in latest update. Unreal.

By "latest update" do you mean macOS Sequoia 15.4 RC2?

(Not to be cynical or anything, but at this point I'm convinced that Apple doesn't consider it a problem or a bug.)

 

[T'hain Esh Kelch]

Has anyone seen if the new LG 45GX950A-B 5k2k OLED display can run 3840x1620 HiDPI?

 

[kikote]

Now where's the person with the M3 Ultra Mac Studio to show us the same test? 🤔

I was about to buy an M3 (Pro or Max) MacBook Pro to avoid this whole shebang but then I found out that the M4 based MacBook Pros have a superior 'quantum dot' display (in addition to having the nano texture screen option that M3 based MacBook Pros don't have), so now I'm even more frustrated than I already was ...

I have an Ultra 3 MacStudio and the LG4025QW. I can run the display with a 3840x1620 HiDpi resolution with 120Hz without any problems. MY notebook - a MacBookPro M3Max can do it as well.

 

[2xmos]

Has anyone seen if the new LG 45GX950A-B 5k2k OLED display can run 3840x1620 HiDPI?

I'd appreciate knowing too!