Is there a question buried in that large paragraph? 😅
Anyway the Dell UP3218K works as intended offering up 7680x4320 pixels or 4K HiDPI with the M2 Pro or M2 Max. It is seen as a single monitor.
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MP All Models SOLVED: 8k Displays Running on Mac Pro? Any? What Video cards would work that support 8k HDMI 2.1/Displayport 1.4/2.0 displays on Mac Pro? YES you can
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Anyway the Dell UP3218K works as intended offering up 7680x4320 pixels or 4K HiDPI with the M2 Pro or M2 Max. It is seen as a single monitor.
> Is there a question buried in that large paragraph? 😅
Sorry - concision not my strength!
> It is seen as a single monitor.
Just to be completely sure (if I'm budgeting for a new MBP): dual-cable UP3218K support is special-cased and appears as a single monitor even if the rest of the system is configured as "Displays have separate Spaces"?
(If it weren't for the apparent synchronisation issue on the M1Max, it would appear as a single monitor so long as it were the only display in the system without any need for special handling, if "Displays have separate Spaces" were disabled.) If the two connections appear as a single monitor separate from any other displays in the system, that's "as intended", and good news.
I still wish the (technically likely easier) 30Hz single-cable mode were enabled (especially if it worked on the MBP I already own...) or that I knew how well an HDMI-to-DisplayPort 8K30p solution would work, since it would integrate better into my setup - but I guess I should be grateful for whatever I get. Except for having to pay Apple for a new computer!
Sorry - concision not my strength!
> It is seen as a single monitor.
Just to be completely sure (if I'm budgeting for a new MBP): dual-cable UP3218K support is special-cased and appears as a single monitor even if the rest of the system is configured as "Displays have separate Spaces"?
(If it weren't for the apparent synchronisation issue on the M1Max, it would appear as a single monitor so long as it were the only display in the system without any need for special handling, if "Displays have separate Spaces" were disabled.) If the two connections appear as a single monitor separate from any other displays in the system, that's "as intended", and good news.
I still wish the (technically likely easier) 30Hz single-cable mode were enabled (especially if it worked on the MBP I already own...) or that I knew how well an HDMI-to-DisplayPort 8K30p solution would work, since it would integrate better into my setup - but I guess I should be grateful for whatever I get. Except for having to pay Apple for a new computer!
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Not sure if you have a specific test you want me to show. But my screen does not really exhibit any ghosting or anything like that. Here is a blow up of the screen looking at MacRumors front page.
can you try this chroma subsampling test image, grey color row:
It is the most noticable on black background.
Also can you please check it with and without VRR? Enabling VRR introduces some kind of compression which affects grey color. Also when I enable GSync on windows, that pink chroma subsampling test image is not showing 4:4:4 anymore.
It photographs way worse than it looks in person, but yea the blue with red does look like poop on the screen. For example, the 'shadow' that shows up for the grey, aqua, white text in the photo, you just do not see with your naked eye. Also the blue the on red, generally shows up much better to your eye than to the photo.
That said, the red text on blue background looks like poop both on the screen and even worse in the photo.
The Red item in a surround like that is the only real artifact that does show up for me in day to day use. But it's strange, in that it's in very limited things. Like here is a screen shot of a watch video with Red lettering inside, and it's fine:
Also for this little red "watched" icon/number, it's really fine too:
But it will in just one case really, look weird (now 2 with your red on blue text sample):
It's the heart tapback in messages, which is, surprise surprise, red on blue. It is a little muddy in the shape.
Anyway, like i said, I know it's hard to believe but you see none of that ghosting with you naked eye, thats a 'feature' of the camera.
That said, something is off when red is buried into blue. I'm guessing that's the lame chroma etc. coming through?
For me, this is truly a great screen because I value the space. It's very easy on the eyes, frankly better than my ancient 30" cinema displays and by a lot. But that artifact is annoying.
So it's still a driver cable thing, I think. I wish I could stop using this weird cable and just plug in the straight HDMI 2.1 to HDMI 2.1 cable I have, and I suspect that would fix it (and likely would in Windows). But it still doesnt work in Ventura last time I tried it (several versions back). I'm going to try it again after I upgrade to Sonoma to pray something improved.
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Oh, and as for VRR, I dont know how to enable or try it. And again, I think this is working with 4:0:0 (or was it 4:2:0), not even 4:2:2, much less 4:4:4
I'd say that this looks pretty similar to mine(QN900B).
You can enable VRR on mac when selecting "Variable (48-60 Hertz)" option. I'm in PC Mode and Game Mode on during this testing. On mac I can also pick HDMI instead of PC, but it seems to be worse
You can enable VRR on mac when selecting "Variable (48-60 Hertz)" option. I'm in PC Mode and Game Mode on during this testing. On mac I can also pick HDMI instead of PC, but it seems to be worse
I dont know where to find that Variable option. I dont see it in Settings>Displays. Also dont see it in SwitchResX.
I am also in PC/Game.
I am using hdmi port on mbp m2 pro and I see it in Settings>Displays after enabling GameMode.(I have input signal plus enabled on that tv port too)
I’m three months in with my Samsung QN700B as a monitor for my Studio. It’s been wonderful.
Pros:
+ Text is sharp. Subpixel effects and ghosting are not seen.
+ 160 ppi is excellent at my usual distance (eyeballs 50-60 inches away from screen).
+ Color seems good to me. I haven’t investigated whether it’s 422 or whatever, but photos look gorgeous.
+ The seemingly endless screen real estate is luxurious. I teach high school classes on Zoom, and it is great to be able to have everything open at once: Zoom, PDFs, ePub books, and all the other apps I might want to look at.
+ The Rectangle app does a great job of managing windows.
+ The price (I paid $1000) is cheap for the pixels and screen size, compared to any monitor offering anything close to this resolution.
Cons:
- The screen is too tall. I tend not to use the menu bar, and spend most of my time looking at windows that I have positioned on the lower 2/3rds of the screen.
- With the screen being so tall, it won’t work to have a webcam on top of the TV. So I have a MagSafe iPhone stand that places my phone in front of the screen and I use it as a webcam via Continuity Camera. This sounds bad, since the phone is standing in front of part of the screen. In practice, however, it’s not a big sacrifice: since there’s so much screen real estate to play with, I don’t miss the few pixels hidden by my phone serving as a webcam.
- The TV does not wake with the Mac, so I have to turn it on manually each time. A real annoyance for those of us coming from an iMac.
- It isn’t quite plug and play. You have to adjust settings and turn on game mode and use VRR in order to avoid some hideous ghosting and nasty effects around text. Not too big a deal, though, since settings are preserved between restarts. Just ”set it and forget it.”
I’m considering mounting it flush on the wall for a cleaner look, especially if I can hide the OneConnect box and the cables for a totally wireless desktop.
I posted my setup on reddit and some dude tried to convince me that a screen this size would ruin my ergonomics. Nothing of the sort has happened. It just sits farther away than my iMac did. Indeed, I used to pull the iMac to the front edge of my desk.
Cleaned up:
![IMG_1143.jpeg]( "IMG_1143.jpeg")
![IMG_1157.jpeg]( "IMG_1157.jpeg")
Candid shot from an actual workday, with cluttered desk and wires visible beneath it. It’s luxurious to be able to blow up a PDF to the size of two 27” 4K displays:
![IMG_1471.jpeg]( "IMG_1471.jpeg")
Pros:
+ Text is sharp. Subpixel effects and ghosting are not seen.
+ 160 ppi is excellent at my usual distance (eyeballs 50-60 inches away from screen).
+ Color seems good to me. I haven’t investigated whether it’s 422 or whatever, but photos look gorgeous.
+ The seemingly endless screen real estate is luxurious. I teach high school classes on Zoom, and it is great to be able to have everything open at once: Zoom, PDFs, ePub books, and all the other apps I might want to look at.
+ The Rectangle app does a great job of managing windows.
+ The price (I paid $1000) is cheap for the pixels and screen size, compared to any monitor offering anything close to this resolution.
Cons:
- The screen is too tall. I tend not to use the menu bar, and spend most of my time looking at windows that I have positioned on the lower 2/3rds of the screen.
- With the screen being so tall, it won’t work to have a webcam on top of the TV. So I have a MagSafe iPhone stand that places my phone in front of the screen and I use it as a webcam via Continuity Camera. This sounds bad, since the phone is standing in front of part of the screen. In practice, however, it’s not a big sacrifice: since there’s so much screen real estate to play with, I don’t miss the few pixels hidden by my phone serving as a webcam.
- The TV does not wake with the Mac, so I have to turn it on manually each time. A real annoyance for those of us coming from an iMac.
- It isn’t quite plug and play. You have to adjust settings and turn on game mode and use VRR in order to avoid some hideous ghosting and nasty effects around text. Not too big a deal, though, since settings are preserved between restarts. Just ”set it and forget it.”
I’m considering mounting it flush on the wall for a cleaner look, especially if I can hide the OneConnect box and the cables for a totally wireless desktop.
I posted my setup on reddit and some dude tried to convince me that a screen this size would ruin my ergonomics. Nothing of the sort has happened. It just sits farther away than my iMac did. Indeed, I used to pull the iMac to the front edge of my desk.
Cleaned up:
Candid shot from an actual workday, with cluttered desk and wires visible beneath it. It’s luxurious to be able to blow up a PDF to the size of two 27” 4K displays:
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Try Menuwhere from Many Tricks if you find going all the way up to the menubar is inconvenient.
This is a very cool idea. Sounds like I could effectively make the bottom half of my screen into an 8k2k ultrawide and leave the top half for “widgets” and rarely used windows?
Any idea how this thing is able to get 2x4k@120hz or 1x8k@60hz? I presume it's doing DSC under the covers?
plugable.com
I'm a stickler for a clean setup, but I really really want an 8k monitor. Contemplating getting a UP3218k and connecting it through that dock for a 1-cable 8K setup to my laptop, but I'm guessing nobody out there has tried that setup.
Plugable USB4 Dual Monitor Docking Station with 4K 120Hz HDMI, 100W Ch
The full power of USB4 is on display in the Plugable 11-in-1 Dual Monitor Docking Station (UD-4VPD). Featuring two HDMI 2.1 ports that support up to 4K 120Hz, to provide crisp, smooth clarity across your HDMI monitor setup. If you really want to pack in the pixels, extend to 1x screen at 8K...
I'm a stickler for a clean setup, but I really really want an 8k monitor. Contemplating getting a UP3218k and connecting it through that dock for a 1-cable 8K setup to my laptop, but I'm guessing nobody out there has tried that setup.
Probably DSC but chroma sub sampling 4:2:0 is also a possibility.Any idea how this thing is able to get 2x4k@120hz or 1x8k@60hz? I presume it's doing DSC under the covers?
Plugable USB4 Dual Monitor Docking Station with 4K 120Hz HDMI, 100W Ch
The full power of USB4 is on display in the Plugable 11-in-1 Dual Monitor Docking Station (UD-4VPD). Featuring two HDMI 2.1 ports that support up to 4K 120Hz, to provide crisp, smooth clarity across your HDMI monitor setup. If you really want to pack in the pixels, extend to 1x screen at 8K...
I'm a stickler for a clean setup, but I really really want an 8k monitor. Contemplating getting a UP3218k and connecting it through that dock for a 1-cable 8K setup to my laptop, but I'm guessing nobody out there has tried that setup.
Dell UP3218K can't get 8K60 from a Thunderbolt dock because it requires two HBR3 connections (it doesn't support DSC) and I think Apple allows that only with the Pro Display XDR. If Apple did allow dual HBR3 for the Dell UP3218K, it would be limited to 48Hz (RGB 8bpc) if the Dell UP3218K even allows anything other than 60Hz from dual HBR3 connection. Actually, the Dell UP3218K has a 48Hz mode dual HBR3 mode but it uses a pixel clock of 856.73 MHz which exceeds the 833 MHz limit that dual HBR3 over Thunderbolt can have (for RGB 8bpc). Dual HBR2 could allow 41Hz but I don't think the Dell UP3218K supports dual HBR2? I believe you'll only get single HBR3 connection for 8K 30Hz from a Thunderbolt dock.
I've no internal knowledge, but possibly the Plugable device is using the optional asymmetric mode in USB4, which would get you 80Gbps unidirectionally - likely they're quoting for USB DisplayPort Alt Mode 2.0 with DisplayPort 2.0, which will hit 8K@60Hz (or quite a bit higher) without needing DSC. I asked Apple about asymmetric support before I got my M1Max system and was told it wasn't supported. I'm sure the UP3218K won't support it, it predates the spec.
FWIW, the UP3218K and the last Intel MBP seem to go way over the DisplayPort nominal bandwidth limit - it claims 7680x4320 10bpp at 30Hz, where I was expecting to have to drop to 24Hz or 8bpp. Either would be absolutely fine for me and leave me with a spare port and possibly external display (Apple flatly refuse to say anything more specific than is on their web site, and I've had tech support refuse to upstream a question because they feel it's answered), but something in the display driver seems to max out at the 6016 pixel width of the Pro Display XDR. (I'll be interested if anyone's managed to drive the Dull U3224KB, which is 6144x3456). I don't really need 60Hz, but the 2x3840x4320 60Hz mode (which pushes the DisplayPort bandwidth as hard as 30Hz full resolution) seems to be the only supported option, and that has stability issues on M1 silicon (which I always assume are something to do with the outputs not being genlocked?) - and that doesn't appear as a single display on my M1Max MBP.
Has anyone had the chance to confirm that the M3 silicon still supports the special dual-head UP3218K mode that got added on M2? Specifically, if I manage to save up for an M3Max (16") MBP, will it solve the problem of the large paperweight on my desk (other than wasting a port to do it)?
Does the custom mode count as two "displays"? I'm currently running 2x4K down one Thunderbolt port and a 5K down another. Even if the UP3218K sucks up two ports, I'm not clear whether I could get a fourth display (alongside the two 4K ones) over HDMI...
FWIW, the UP3218K and the last Intel MBP seem to go way over the DisplayPort nominal bandwidth limit - it claims 7680x4320 10bpp at 30Hz, where I was expecting to have to drop to 24Hz or 8bpp. Either would be absolutely fine for me and leave me with a spare port and possibly external display (Apple flatly refuse to say anything more specific than is on their web site, and I've had tech support refuse to upstream a question because they feel it's answered), but something in the display driver seems to max out at the 6016 pixel width of the Pro Display XDR. (I'll be interested if anyone's managed to drive the Dull U3224KB, which is 6144x3456). I don't really need 60Hz, but the 2x3840x4320 60Hz mode (which pushes the DisplayPort bandwidth as hard as 30Hz full resolution) seems to be the only supported option, and that has stability issues on M1 silicon (which I always assume are something to do with the outputs not being genlocked?) - and that doesn't appear as a single display on my M1Max MBP.
Has anyone had the chance to confirm that the M3 silicon still supports the special dual-head UP3218K mode that got added on M2? Specifically, if I manage to save up for an M3Max (16") MBP, will it solve the problem of the large paperweight on my desk (other than wasting a port to do it)?
Does the custom mode count as two "displays"? I'm currently running 2x4K down one Thunderbolt port and a 5K down another. Even if the UP3218K sucks up two ports, I'm not clear whether I could get a fourth display (alongside the two 4K ones) over HDMI...
The 6K Dell should work fine with the M1 Max. The 8K Dell requires at minimum M2 Pro or M2 Max (and takes up two TB4/USB4 ports, ugh).
I upgraded to M2 Max simply because of that.
Should it? I had a chat with the author of SwitchResX, and understood that the maximum display resolution that can be fed in has a width of 6016 pixels. That seemed a very arbitrary number and likely hacked in solely because it's exactly the size of the Pro Display XDR. The Dell is, for some reason, slightly larger, which made me wonder whether it would work (and indeed how). Dell do list it as compatible with macOS, but that might just mean it worked with an old Intel mac, or they may just be making an assumption. Or I could be worrying about nothing - I just wondered if anyone had confirmed it. (Since Apple's technical support refuse to ask questions of their developers on my behalf.)
Yup, and were I a bit richer I'd have done the same.
Having put it off, the M3Max is more tempting, particularly from a performance upgrade perspective. But I wouldn't put it beyond this having slipped through the cracks as part of the M3 design, so, again, I just wanted to check whether someone had actually confirmed it still works. (I've not found any Apple documentation which confirms the support for the UP3218K, or 8K at all except over HDMI, so I can't get Apple's customer facing teams to make a statement even for the M2. Before I got the M1 I was assured that the Thunderbold/Displayport connection was at least as capable as on my Intel MBP, so "it should work" doesn't make me spend £5000...)Yes, the Dell U3224KB works fine on M1 Pro and M1 Max at the correct resolution (6144 x 3456 / 3072 x 1728 HiDPI).Should it? I had a chat with the author of SwitchResX, and understood that the maximum display resolution that can be fed in has a width of 6016 pixels. That seemed a very arbitrary number and likely hacked in solely because it's exactly the size of the Pro Display XDR. The Dell is, for some reason, slightly larger, which made me wonder whether it would work (and indeed how). Dell do list it as compatible with macOS, but that might just mean it worked with an old Intel mac, or they may just be making an assumption. Or I could be worrying about nothing - I just wondered if anyone had confirmed it. (Since Apple's technical support refuse to ask questions of their developers on my behalf.)
Yup, and were I a bit richer I'd have done the same.
There is a 33 page thread here about the Dell 6K U3224KB Monitor.
Cool - useful to know. My understanding was that the resolution support by SwitchResX was just determined by messing with the support files and seeing what was rejected, so it may be that 6144 just wasn't tried as a resolution. Interesting that Apple supports something bigger than their own display but still doesn't support 7680 pixels. (I think I'd once tried hard-wiring some subset of 7680 in the hope of getting a slightly pillarboxed screen and failed, but I didn't try very hard.)
Thanks!
Asymmetric mode requires USB4 v2 or Thunderbolt 5. I don't think anything supports that yet?
Dell UP3218K has these 8K options:
- 7680x4320 24Hz using one 826.26 MHz connection.
- 7680x4320 30Hz using one 1030.25 MHz connection.
- 7680x4320 48Hz using two 856.73 MHz connections.
- 7680x4320 60Hz using two 1058.80 MHz connections.
864MHz is the max allowed by 10bpc RGB which means the 30Hz and 60Hz modes must be limited to 8bpc RGB (max 1080 MHz).
The EDID says it can do 4:2:2 chroma sub sampling. Maybe it can do 10bpc RGB using 4:2:2 chroma sub sampling for the 30Hz and 60Hz modes?
The dual tile mode of the UP3218K should not count as two displays because dual tile displays count as a single display on Apple Silicon Macs. The LG UltraFine 5K is a dual tile display and it works on M1 Macs which only support a single display from Thunderbolt.
There may be an issue with total pixels per second where Apple says a Mac can connect n 4K displays but only n-x 6K displays. Maybe it's DSC related. The Dell doesn't use DSC but its two halves each use almost twice as much bandwidth as 4K. I haven't seen this issue get explored. I remember someone used three XDRs (using dual tile mode) with a Vega II (can support 6 displays) in a Mac Pro even though Apple says it can only support two XDRs.
https://forums.macrumors.com/threads/psa-pro-vega-ii-single-can-power-3x-xdr-displays.2225758/
I wonder if it can support three UP3218K's? It's an Intel Mac so each dual tile display counts as two displays.
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@joevt, what f&*%$ng industry do you work in that your knowledge of....whatever you call it (connectivity standards?)...is so damn thorough. I routinely stumble upon your posts in other threads and they're always some of the most thorough and technical posts I see here.
I presume you're not referring to standard displays though, because I'm currently running 2x4k's through a single Thunderbolt connection via this guy to my M1 Max.
Being a hub, I wondered if it was passive enough that it would "just work" - or that the implementers *think* it would and just never tried it (assuming that everything specified will magically be fine is not unheard of in marketing). But I could be maligning them. I'd thought asymmetric mode was older (I remember it being announced as a USB4 feature before I got my M1Max MBP, because I asked Apple whether they supported it - they didn't...) but it may have been in a press release before it was fully standardised.
That's why I was confused - the MBP display info screen swore blind it was a 10-bit panel (like the two UltraFine 4Ks, which are collectively using the same bandwidth over two links). I initially wondered if the Mac was using a 10-bit internal framebuffer and dithering it to 8-bit in the display controller (I tried a screen grab to prove it, but of course that was 8-bit PNG regardless...) but if that was the solution, it wouldn't explain why the internal display was only 8-bit - this on my Intel/AMD MBP.
The OSD reported the refresh rate and resolution; I've just fired up my old computer to check, and the OSD says "input color format RGB" (7680x4320, 30Hz). SwitchResX reports billions of colours. (I think the MacOS UI used to as well, but updates made it harder to find.) I'd be fine to switch between the 24 and 30Hz depending on whether I want higher bit depth (I did set up some gradients to see if I could tell on the display, but it's a mild pain to make out); 30Hz and 30bpp was a nice bonus. It might just be over driving the clock and both ends happen to work?
Ah - I assumed the limit was a hardware one on separate display controllers and the tiles needed reading from separate blocks of memory. I actually didn't realise the UltraFine 5K was a dual tile display - I assumed it was just using HBR3, since that should be enough bandwidth for 60Hz 30bpp. Live and learn.
The 6K displays would still need splitting, but I assumed they were special cased. Somehow I'd missed that the M1 could drive the 6K display, or forgotten that I thought it was odd - I could believe it being easier on the display controller if it's offering paired pixels across two channels, similar to the old T220 pixel interleaving.My grumble about the UP3218K is that I only want it to be a single display and I'm perfectly fine with it being at lower refresh rate, but I think that's stuck in an M1 display driver limitation, and I'm not expecting fixes at this point. I've tried every route I can, and suspect the answer is now "buy an M3".
I assume at some point one runs into the bandwidth limit of the interface. What Apple are prepared to admit they support on their web site and what the hardware can actually do are very different things, as this thread shows. Unfortunately what they "support" is what the customer-facing people are prepared to talk about, with nothing more specific. Thank you, this forum!
(Also, belated, thanks Pressure for the thread on the U3224KB - I dropped in to ask for M3 updates and failed to check whether my off-hand question was already thoroughly answered. Sorry about that!)
Speaking as someone working for a GPU manufacturer, I'll second the thanks for the informed response, joevt! (It's been a while since I touched display controller hardware though, so apologies for my novice mistakes.)
Presumably "M1 Macs" != "M1 Max". The Max (etc.) supports more separate displays, I assumed because of additional display controllers doing the framebuffer read-out. I'm running two LG Ultrafine 4Ks down one Thunderbolt cable, but I believe it's two separate Thunderbolt channels each of which is running in DisplayPort mode (as distinct from some PC adaptors that run DisplayPort over Thunderbolt and then use MST to present two displays - which at least historically Apple hasn't exposed in macOS, even though IIRC it works under Windows on an Intel MBP). I assume the Plugable is separating the Thunderbolt streams (where the Ultrafines are set up to daisy-chain so I don't need an external box).
That said, unless it really is a bandwidth issue, there's a special display mode in the 6K, or symmetrical outputs help (maybe one timing controller?) I don't really know why an M1 would be able to support a dual-tile display but not be able to support two monitors.