Using your MacBook with the new LG UltraFine 4K display (USB-C)

mathpunk

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Jan 31, 2015
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http://www.apple.com/shop/product/HKMY2LL/A/lg-ultrafine-4k-display?fnode=8a

Interesting news today, as it appears both (?) 2016 and 2015 models can take advantage of this new LG display. I guess the display negotiates the USB-C link to drop down the channels to dual USB 2.0 in order to allow enough bandwidth for 4K.

Who's getting one?
Looks awesome! I've been waiting for a 21" 4K display to show up. I had the 27" Thunderbolt Display for years that I used with a MacBook Air, and I actually found it too big. Once I went retina with the 12" MacBook, I could never go back to a non-retina display. So, for retina I think the 4K 21.5" is perfect for a desktop display, and I will probably order one of the new LGs next month.
 

BeatCrazy

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where does it say 2015 rMB specifically?
Under System Requirements it says "USB-C-enabled Mac". And the product description specifically references MacBook (in addition to MacBook Pro) several times.

How is this better than other 4k displays that support USB-C?
It seems to imply that the 2015/2016 MacBooks will display 4K at 60Hz.
 

thadoggfather

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Oct 1, 2007
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Under System Requirements it says "USB-C-enabled Mac"



It seems to imply that the 2015/2016 MacBooks will display 4K at 60Hz.
i would personally want explicit confirmation of 2015

afaik 2015 isn't capable of 60hz 4k, only 30hz unless this display works some magic hence my skepticism
 

BeatCrazy

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i would personally want explicit confirmation of 2015

afaik 2015 isn't capable of 60hz 4k, only 30hz unless this display works some magic hence my skepticism
The 60Hz 4K support is implied, because the associated USB ports on the LG are limited to USB 2.0. And we know that the MacBook's USB-C throughput can support 4K @ 60Hz if you knock down the USB data lanes to 2.0.

Both Intel Iris 5300 and Iris 515 (MacBook 2015 and 2016 respectively) can support 4K @ 60Hz, it's always been the USB-C w/USB 3.0 support that throttles the video.
 
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thadoggfather

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i haven't kept up, thanks!

it would be cool for someone to try the 21,5" with 12" combo

5-6 weeks wait, yikes
 

BeatCrazy

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i haven't kept up, thanks!

it would be cool for someone to try the 21,5" with 12" combo

5-6 weeks wait, yikes
Well for sure it works, because it explicitly says "MacBook", and "USB-C-enabled Mac". Can't describe the 2015/2016 MacBooks any more succinct than that!

I currently use 4 computers connected to my Dell U2413 monitor, including my 2016 MacBook via the CalDigit USB-C dock. I'm not aware of any USB-C adapter that would allow me to switch between HDMI/DVI/DP like I do via separate inputs on my Dell today. Too bad!
 

BeatCrazy

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I have a 2015 Macbook and with an LG 27UD88-W. With the Sierra update you can choose 4k native in the OS although I think you'd be crazy to do that on 21" display. I usually run it at 2560x1440 or 1080P high DPI mode.
Was it the 10.12.1 update that made this possible? The new LG monitor specifically requires 10.12.1, so I'm wondering if Apple did some jiggery pokkery with this latest update to enable 4K on the standard MacBooks, similar to what that patch/hack has been doing.
 
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daijholt

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It does appear to be compatible with MacBook 12". The 4K model says compatible in the Apple Store app (my MacBook is called ShadowGold)

The 5k model says nothing however, so that looks to be Pro exclusive.
 

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BeatCrazy

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It does appear to be compatible with MacBook 12". The 4K model says compatible in the Apple Store app (my MacBook is called ShadowGold)

The 5k model says nothing however, so that looks to be Pro exclusive.
As expected. 5K takes serious GPU power.
 

iDemiurge

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Feb 7, 2011
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I'm honestly surprised with this. If it does indeed support full res at 60 Hz on the 2015 mb I'll be really tempted to get one. It also seems to have speakers, but does anyone know whether it has audio out?
[doublepost=1477688264][/doublepost]
I have a 2015 Macbook and with an LG 27UD88-W. With the Sierra update you can choose 4k native in the OS although I think you'd be crazy to do that on 21" display. I usually run it at 2560x1440 or 1080P high DPI mode.
At 60 Hz?
 

iDemiurge

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Feb 7, 2011
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Yes, at 60Hz but trust me you're not going to want to run it at native 4K resolution (everything is so tiny.) OSX first started giving me the option to run native 4K when I installed the Sierra update. I was using the patch previously. Please read this full thread if you're truly interested in the history...

https://forums.macrumors.com/thread...tors-cables-adapters-that-work.1974167/page-4
Thanks, that's real interesting. I had heard about the patch but thought it was for the 2016 model only (or I guess the patch was indeed made only for the 2016 model). But Sierra seems to have enabled 4k@60hz on both the 2016 and 2015, without need for any patch, as you confirm.

I know 4k native is crazy cause it'd all look too tiny, but you do suggest it works in hi dpi mode, right? Is performance too dreadful/stuttery compared to what you get on the main screen without any external monitor attached?
 

Dunbar

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Jun 25, 2010
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I know 4k native is crazy cause it'd all look too tiny, but you do suggest it works in hi dpi mode, right? Is performance too dreadful/stuttery compared to what you get on the main screen without any external monitor attached?
The patch actually worked on my 2015 Macbook. No stuttering that I've noticed. The only hiccup is if you unplug your Macbook from the monitor a lot it sometimes you have to reboot to be able to select the scaled monitor resolutions. Keep in mind I have a 27" monitor but yes 1080P hi dpi looks good but doesn't really take advantage of the larger monitor real estate. I love that you can do 2560x1440 with Sierra as that gives you more real estate to work with (albeit with smaller text.) Honestly Apple has some catching up to do with scaling the UI to 4K. Windows 10 handles it better.
 
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bluewooster

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Jul 18, 2007
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Does the patch not work if you have already upgraded to Sierra?

I bought a 4k monitor and hooked it up with the provided HDMI cable and the Apple Digital AV Adapter. I only have 4k at 30 Hz as an option - no options for hi dpi scaling. If I use a software solution, I can have 1080p hi dpi at 30 Hz.

I tried the patch (and disabled SIP first using the instructions on the 9to5 site) but it gives me multiple error messages when I run it in terminal (I gave it permission with chmod +x first).

I was hoping that Sierra would give me various hi dpi options (1440p would be perfect) without needing to patch anything. Is there something else I should try before returning the monitor?

(This is the monitor if that matters)
 

BeatCrazy

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Why buy that new 4k monitor which is 21.5 inches when there is already LG27UD88 which is also 4k and 27 inches?
My theory is that there is some trickery with macOS 10.12.1 and the 21.5" UltraFine version (only) that allows for 4K @ 60Hz from a MacBook with no hacking.
 
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