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LG's New UltraFine 5K Display Limited to 4K Resolution When Used With 2018 iPad Pro

LG yesterday released a new version of its UltraFine 5K Display with USB-C connectivity, allowing it to be used with 2018 iPad Pro models, but Apple has since confirmed that the iPad Pro cannot take advantage of the full 5K resolution.


In a new support document, Apple says the UltraFine 5K is limited to a 4K resolution of 3,840×2,160 at 60Hz when connected to 2018 iPad Pro models via USB-C. The full 5K resolution requires a 2016 or newer MacBook Pro, a 2018 or newer MacBook Air, a 2017 or newer iMac or iMac Pro, or a 2018 Mac mini.

The new UltraFine 5K Display is available to order for $1,299.95 on Apple.com. Like the previous model, it also supports Thunderbolt 3, with up to 94W of power for pass-through charging of any Mac or iPad connected to the display.

The new display has the model number 27MD5KL-B.

Related Roundup: iPad Pro
Tags: LG, UltraFine


Top Rated Comments

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4 weeks ago
Well that's not a surprise - I'm pretty sure standard USB-C can't carry a 5k 60hz signal, it's not in the spec for starters.
Rating: 21 Votes
4 weeks ago

Imagine having the most svelte and streamlined tablet on the market connected to a fugly bezel-thick monitor that looks like it came out of a ca. 2007 accounting firm. The resolution would be the least of my concerns.

While using it, are you going to look at the screen or at the bezels? The resolution is imho more important.

The monitor is not a beauty, though.
Rating: 21 Votes
4 weeks ago

Provoke all you want, but Apple WAS about both form and function. Think Cinema Display (RIP). Speaking as a design director who's been working all day with Macs for the last couple decades and can afford to buy the whole lineup a few times over. I'd rather buy something that doesn't offend my eyes. What's your point exactly?

Steve, you are so missed.

This isn't an Apple product. Calm down.
Rating: 12 Votes
4 weeks ago
Imagine having the most svelte and streamlined tablet on the market connected to a fugly bezel-thick monitor that looks like it came out of a ca. 2007 accounting firm. The resolution would be the least of my concerns.
Rating: 10 Votes
4 weeks ago

it has not enough bandwidth , since tb3 is still under Intel license

www.displayport.org ('http://www.displayport.org') states that technically, USB-C can now support 5K resolution.

https://www.displayport.org/displayport-over-usb-c/


DisplayPort leverages the Alternate Mode Functional Extension of the USB Type-C interface, and shares similar electrical characteristics with USB 3.1, allowing use of common system elements.


* Video, SuperSpeed USB and power, all on one connector
* 4K @60Hz 24-bit color (without compression) with simultaneous USB 3.1
* 5K (5120 x 2880) display support without compression with simultaneous USB 2.0
* Support for BT.2020 color space, HDR, and HDCP 2.2
* 8K x 4K display support with use of 4:2:0 pixel structure (good) or VESA Display Stream Compression (better)
* High-end multichannel audio support
* Backward compatible with VGA, DVI, and HDMI 2.0 with CEC using plug adapters or adapter cables
* Extensible packet-based data structure



It's just that the 2018 iPad Pro models or the 12" MacBooks can't do it.

However, simultaneous 5K video plus USB support over USB-C is limited to USB 2.0. To get simultaneous 5K + USB 3, you need to use Thunderbolt.


So to be clear the previous generation 5K display was unable to handle an iPad Pro 2018 connected to it? Can anyone verify this? I've read the previous generation 4K display worked fine with iPad Pro 2018.

The previous 5K display is Thunderbolt 3 only. It didn't work at all with the iPad Pro. The previous 4K display is USB-C. The new 5K display accepts both Thunderbolt 3 and USB-C inputs.
Rating: 8 Votes
4 weeks ago
Ugly bezels. Looks like cheap plastic casing, too.
Rating: 7 Votes
4 weeks ago
It’s Tim’s fault obviously;)
Rating: 6 Votes
4 weeks ago

So, $1300 for a 27" 4K monitor? LG is drunk off of the Apple Kool-Aid. They should have renamed it UltraFine 5K*.

No. It's a 27" 5K monitor.

I know you're trying very hard to diss this monitor, but you've failed miserably with your specific argument here.
Rating: 6 Votes
4 weeks ago

Well that's not a surprise - I'm pretty sure standard USB-C can't carry a 5k 60hz signal, it's not in the spec for starters.

It is just a connector. What it can carry depends on the alternative mode.

it has not enough bandwidth , since tb3 is still under Intel license

www.displayport.org ('http://www.displayport.org') states that technically, USB-C can now support 5K resolution.

What does any of your above rant have to do with the fact that USB doesn’t have sufficient bandwidth to support 5K? Or did you post to the wrong thread?


5k @ 60Hz needs either two DisplayPort 1.2a cables (8 lanes) in 'MST' mode (where each cable drives half of the screen) ...or a single DisplayPort 1.4 cable (4 lanes - faster speed), but in the latter case the computer's GPU, monitor and the USB-C/TB controller all need to support DisplayPort 1.4 and single-stream 5k.

Until last year, Thunderbolt controllers didn't support DisplayPort 1.4 at all, but since Thunderbolt has a higher bandwidth and multiplexes DisplayPort and PCIe data into a single stream that can use all of the wires in a USB-C cable, it could fit two 'virtual' DisplayPort 1.2 streams on a single cable and drive a 5k display in MST mode.

USB-C alt mode (i.e. a non-TB display and/or a non-TB computer connected via USB) simply works by 'switching' some of its 4 high-speed data wires to carry raw DP signals, and has always supported DisplayPort 1.4 on paper, but that doesn't mean that all USB-C controllers support it - none of teh early implementations did, the Intel controllers in pre-2018 Macs don't, and its irrelevant to the 13" MBP and Air because their Intel iGPUs don't.

Maybe the iPad Pro can output 5k DisplayPort 1.4 over USB-C, maybe it can't, but the odds are that the LG display only implements it via 2xDP1.2-over-Thunderbolt, because most of the Macs out there can't do DP.1.4.

(Presumably Apple's new $1k XDR display stand can use DP1.4, at least over Thunderbolt, but you need the optional $5k display for that).


So to be clear the previous generation 5K display was unable to handle an iPad Pro 2018 connected to it? Can anyone verify this? I've read the previous generation 4K display worked fine with iPad Pro 2018.


The previous version of the 4k was USB-C DisplayPort Alt Mode only, and would work with an iPad or 12: MB, while the previous 5k was Thunderbolt only and would only work with a MBP or Air. Pre-2018, unlike the 'host' ports on computers, the socket on a peripheral device could only be one or the other - but the latest Thunderbolt controllers fixed that.

Both of the revised displays now have dual mode inputs that can work in either Thunderbolt or USB-C Alt Mode.
Rating: 5 Votes
4 weeks ago

But nothing is as beautiful and aethetically pleasing as apple stuff. Nothing.

Third World Problems.


Yeah they look great but throttle the minute you do real work on it. Look how great my flaming slate is!!!

The fact that people here are obsessing about the look of this monitor rather than the 5k demonstrates 1) these people care only for aesthetics 2) dont do actual work on their computers 3) probably can’t afford the display in the first place.


Provoke all you want, but Apple WAS about both form and function to an impeccable degree. Think Cinema Display (RIP). Speaking as a design director who's been working all day with Macs for the last couple decades and can afford to buy the whole lineup a few times over. I'd rather buy something that doesn't offend my eyes. What's your point exactly?

Steve, you are so missed.
Rating: 5 Votes

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