LG UltraFine 5K - Owners Thread

AppelGeenyus

macrumors member
Nov 3, 2019
33
29
Hi. I finally unpacked the 5K and hooked it up to the left-most TB port on my Mac Mini. I have an eGPU with a Radeon 580 on the right most port. I have designated the LG 4K monitor I have as my primary, as I understand that it leads to higher likelihood that both displays use the eGPU? Not sure that's correct.

I have also gone through and updated the Get Info preferences on a bunch of key apps to preference the eGPU. But I still felt like I was getting some choppy scrolling.

I then went ahead and watched a 4k 60Hz video on YouTube via Firefox (also with preference eGPU box set).

Notably, in GPU History in System Monitor, the eGPU was clearly working with pretty high blue bars. The video was really nice and smooth on the 4K (which is connected via DisplayPort to the eGPU). But when I moved it over to the LG 5K, lots of frames were dropped. Nonetheless, the GPU History continued to seem like the eGPU was being used.

Is this just a function of having that many more pixels to push (for the exact same content)? I would have thought that a reasonable GPU like the Sapphire Radeon 580 would be more than enough for something like that. Or am I not really getting the eGPU to work?

The screen is beautiful to look at, but concerned this set up is a fail, if I can only use the internal GPU...

Thoughts? Has anyone had experience with set-eGPU?

Thanks!

EDIT: One additional note. I have a Akitio TB3 box with my User drive attached to the TB3 port next to the eGPU. Is that a mistake? What would be optimal if I have:

1. LG 5k Ultrafine
2. Akitio 4 drive TB3 enclosure
3. Razer Core eGPU enclosure

Thanks again.
Regarding youtube, anything above 1080p uses VP9 codec instead of H.264. Apple does not support hardware decoding of VP9 in MacOS, so when you watch 4K videos on youtube they are decoded in software on your CPU.

To get the most performance from an eGPU, your monitors should be connected directly to the eGPU, otherwise the video signal has to be routed back into your system then passed to your monitors. I think the performance loss averages ~15% but can be higher. You could try connecting the 5K monitor to your eGPU with an adapter cable like this one, but I have no idea if that actually works. Otherwise you are stuck connecting the 5K directly to your Mac, and you should at least connect your 4K monitor directly to the eGPU, which should work even with an adapter cable(if required).

The four TB3 ports on your Mac mini share two controllers(one for each pair), so you would probably want your eGPU on one pair, and your akitio drive on the other pair. And if you do have to keep your 5K connected directly to your Mac then it's up to you to determine which side should take the performance hit.
 
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joevt

macrumors 6502a
Jun 21, 2012
825
409
and all of the monitor reporting utilities I can find indicate that it's running at 5K.
You need to run SwitchResX, and double-click the current resolution in the Current Resolutions tab of the display in SwitchResX to view the timing info. It will show Pixel Clock, Active, Scan rate, and Scale to.

You'll probably see 4K which has: Pixel Clock: 533 MHz; Active: 3840x2160; Scan rate: 133 kHz, 60Hz; Scale to: 5120x2880. That's for Looks Like 2560x1440 mode (HiDPI mode). The Scale To dimensions is twice as tall and wide as the Looks Like numbers for Retina (HiDPI) modes.

If you were running at 5K, then the Pixel Clock would be something around 938 MHz.

I have a Akitio TB3 box with my User drive attached to the TB3 port next to the eGPU. Is that a mistake? What would be optimal if I have:

1. LG 5k Ultrafine
2. Akitio 4 drive TB3 enclosure
3. Razer Core eGPU enclosure

Thanks again.
I think LG and Akitio connected to one Thunderbolt controller, and Razer connected to the other; for example: 1,2,3

At least Akitio and Razer should be on different Thunderbolt controllers because they both use PCIe tunnelling.
 

gadgetfreak98

macrumors regular
Feb 6, 2009
164
52
You need to run SwitchResX, and double-click the current resolution in the Current Resolutions tab of the display in SwitchResX to view the timing info. It will show Pixel Clock, Active, Scan rate, and Scale to.

You'll probably see 4K which has: Pixel Clock: 533 MHz; Active: 3840x2160; Scan rate: 133 kHz, 60Hz; Scale to: 5120x2880. That's for Looks Like 2560x1440 mode (HiDPI mode). The Scale To dimensions is twice as tall and wide as the Looks Like numbers for Retina (HiDPI) modes.

If you were running at 5K, then the Pixel Clock would be something around 938 MHz.


I think LG and Akitio connected to one Thunderbolt controller, and Razer connected to the other; for example: 1,2,3

At least Akitio and Razer should be on different Thunderbolt controllers because they both use PCIe tunnelling.
This actually was how I had it, as it turns out.

Would it be beneficial to put the LG 5K through the Akitio's own TB3 port? e.g.,

Left to right:

Port 1: Razer X
Port 2: A Belkin TB3 dock (with a USB-C drive attached)
Port 3: empty
Port 4: Akitio enclosure (with LG 5K daisy chained)

thoughts? Thanks. Watching the GPU History like a hawk to see what's the story...
- - Post merged: - -

Further... It's clear that with the setup described above (and even with prefer eGPU selected), when I go in and out of full screen multiple times with the 5K in the Notes app, it is taxing the internal GPU. When I move Notes to the 4K screen connected to the DisplayPort on the eGPU, it is pushing the RX 580. So does the "prefer eGPU" really do anything? Is there something more I need to do to actually make it work that way? Thanks!
 
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joevt

macrumors 6502a
Jun 21, 2012
825
409
Port 4: Akitio enclosure (with LG 5K daisy chained)
LG display takes 26.5 Gbps leaving only 13.5 Gbps for writes to the Akitio. How fast is the Akitio when it is by itself? How fast is the USB-C drive when it is by itself?
Just keep in mind there is 40 Gbps total per Thunderbolt port but only 22 Gbps for PCIe traffic (maybe 23 Gbps for PCIe traffic for both ports of a Thunderbolt controller together).
 

AppelGeenyus

macrumors member
Nov 3, 2019
33
29
This actually was how I had it, as it turns out.

Would it be beneficial to put the LG 5K through the Akitio's own TB3 port? e.g.,

Left to right:

Port 1: Razer X
Port 2: A Belkin TB3 dock (with a USB-C drive attached)
Port 3: empty
Port 4: Akitio enclosure (with LG 5K daisy chained)

thoughts? Thanks. Watching the GPU History like a hawk to see what's the story...
- - Post merged: - -

Further... It's clear that with the setup described above (and even with prefer eGPU selected), when I go in and out of full screen multiple times with the 5K in the Notes app, it is taxing the internal GPU. When I move Notes to the 4K screen connected to the DisplayPort on the eGPU, it is pushing the RX 580. So does the "prefer eGPU" really do anything? Is there something more I need to do to actually make it work that way? Thanks!
Your only real solution is to get a Blackmagic eGPU which has a TB3 output that's designed to handle a 5K display with full acceleration, then connect a second 4K monitor to its HDMI output(or Displayport if you get the Pro version).
 

gadgetfreak98

macrumors regular
Feb 6, 2009
164
52
Thanks. That's what I feared. If I don't get the pro (which is crazy expensive), would the 4k work ok on the HDMI port? Or am I going to lose out with that...

Interestingly, the non-pro is sold out online for 10-12 weeks. Available in some stores though...
 

AppelGeenyus

macrumors member
Nov 3, 2019
33
29
If the 4K is an Ultrafine I have no idea sorry, any other monitor with hdmi would work. Thunderbolt/usb-c only monitors and eGPUs are not a good mix.
 

Ledgem

macrumors 68000
Jan 18, 2008
1,842
590
Hawaii, USA
You need to run SwitchResX, and double-click the current resolution in the Current Resolutions tab of the display in SwitchResX to view the timing info. It will show Pixel Clock, Active, Scan rate, and Scale to.

You'll probably see 4K which has: Pixel Clock: 533 MHz; Active: 3840x2160; Scan rate: 133 kHz, 60Hz; Scale to: 5120x2880. That's for Looks Like 2560x1440 mode (HiDPI mode). The Scale To dimensions is twice as tall and wide as the Looks Like numbers for Retina (HiDPI) modes.

If you were running at 5K, then the Pixel Clock would be something around 938 MHz.
Interesting, thanks. It is as you described (also cross-checking against the internal display) so it must be 4K that is scaling. It's pretty impressive, I really can't see a difference between it and my built-in iMac screen.

This actually was how I had it, as it turns out.

Would it be beneficial to put the LG 5K through the Akitio's own TB3 port?
I read a case of someone using the Akitio Node Duo and inserting a graphics chip into one slot, and a Thunderbolt controller (I can't remember if they went with Titan Ridge or Alpine Ridge) into the other slot. That seemingly emulated the BlackMagic Pro. As far as I've been reading around, it's better to plug the monitor into the eGPU setup directly, although there have been some cases of the monitor not consistently coming on when the system comes out of sleep with such a configuration.
 

joevt

macrumors 6502a
Jun 21, 2012
825
409
I read a case of someone using the Akitio Node Duo and inserting a graphics chip into one slot, and a Thunderbolt controller (I can't remember if they went with Titan Ridge or Alpine Ridge) into the other slot. That seemingly emulated the BlackMagic Pro.
I don't think it matters which Thunderbolt add-in card is used. It allows the Thunderbolt display to work but macOS can't communicate with the USB devices in the Thunderbolt display in that configuration so the USB ports won't work and neither will brightness control. The software doesn't exist yet to enable PCIe tunnelling in the add-in card to allow communication with the USB controller in the display.
 

gabe211

macrumors member
Dec 27, 2011
68
10
Hey all so my LG 5K has completely died after about two years. Connecting it to my MPB does absolutely nothing. No charging or display.

Whose at fault? My cat! My nest cam has a view of my desk, after I left you could clearly see him sitting on the keyboard, looking down, and then deciding to give the TB3 cable a bit of a chew... then bam! The display went black. I was only away for a few minutes :(

I thought no big deal, maybe the TB3 cable got damaged, but after purchasing a new one it was the same result. Even tried on some different TB3 MacBooks.

Don't know too much about electric components, but maybe there was a short circuit? Power supply fried? Who knows. Also a bit concerning that my cat is wanting to chew active power cables. Kitty didn't look hurt, or react as soon as the screen went black so not sure if there was a electric jolt.

Contacted LG and initiated a repair. They quoted me a $450(!) for an out of warranty repair fee, but at this point I don't know what else I can do. Going to ship it out soon and see what happens.

Keep your cats away from cables/electricity 😅
 

flipcide

macrumors newbie
Jan 30, 2020
1
0
Hey all so my LG 5K has completely died after about two years. Connecting it to my MPB does absolutely nothing. No charging or display.

Whose at fault? My cat! My nest cam has a view of my desk, after I left you could clearly see him sitting on the keyboard, looking down, and then deciding to give the TB3 cable a bit of a chew... then bam! The display went black. I was only away for a few minutes :(

I thought no big deal, maybe the TB3 cable got damaged, but after purchasing a new one it was the same result. Even tried on some different TB3 MacBooks.

Don't know too much about electric components, but maybe there was a short circuit? Power supply fried? Who knows. Also a bit concerning that my cat is wanting to chew active power cables. Kitty didn't look hurt, or react as soon as the screen went black so not sure if there was a electric jolt.

Contacted LG and initiated a repair. They quoted me a $450(!) for an out of warranty repair fee, but at this point I don't know what else I can do. Going to ship it out soon and see what happens.

Keep your cats away from cables/electricity 😅
More than likely this wasn't your cat's fault. I had mine go dead 9 months ago. I sent it in for repair (back then they only wanted $159 for diagnostics/repair). The work order said they replaced the main board part# EBU63798701. When I got it back it worked great until a few days ago when I was rearranging my desk and simply straightened out the Thunderbolt 3 cable while it was plugged into my MacBook Pro. Then the screen flickered a couple of times and went dead again just like before. Now I've got no display, no charging, etc.

I think there's a defect with either the Thunderbolt 3 cable they send with the unit or the mainboard or both. My setup is pretty static. Nothing ever moves or changes, so it's not not like this $1K+ monitor was abused or mishandled in any way. The fact the price for repairs has now shot up to $450 gives me the impression that these units are starting to fail with the same issue more and more and they're trying to keep costs under control.

When I called LG I pushed back on paying for repairs and they're supposedly in the process of considering a "one-time courtesy repair" but I'm still waiting to hear back.
 

syndr0me

macrumors regular
Sep 17, 2014
101
68
I've got one of the monitors that came out shortly after the wifi fix. I've noticed lately that it's extremely sensitive to static discharge. The screen will go black for 5-20 seconds if there's any static discharge nearby. Like, it doesn't even have to touch the monitor. It happens when I touch my _wireless_ Apple keyboard. Most frequently it happens when I put my phone on the base of the stand as I'm sitting down in my chair and there's discharge into the base.
 

gabe211

macrumors member
Dec 27, 2011
68
10
More than likely this wasn't your cat's fault. I had mine go dead 9 months ago. I sent it in for repair (back then they only wanted $159 for diagnostics/repair). The work order said they replaced the main board part# EBU63798701. When I got it back it worked great until a few days ago when I was rearranging my desk and simply straightened out the Thunderbolt 3 cable while it was plugged into my MacBook Pro. Then the screen flickered a couple of times and went dead again just like before. Now I've got no display, no charging, etc.

I think there's a defect with either the Thunderbolt 3 cable they send with the unit or the mainboard or both. My setup is pretty static. Nothing ever moves or changes, so it's not not like this $1K+ monitor was abused or mishandled in any way. The fact the price for repairs has now shot up to $450 gives me the impression that these units are starting to fail with the same issue more and more and they're trying to keep costs under control.

When I called LG I pushed back on paying for repairs and they're supposedly in the process of considering a "one-time courtesy repair" but I'm still waiting to hear back.
That's concerning. My monitor came back and is fully working again. Thankfully, the initial support person must've been mistaken as I was only charged $159.38 for the repair. Their repair notes only mentioned "lit screen but No picture" and "Part replaced-electrical". So I'm guessing the board must've been replaced. Hopefully it doesn't happen again down the road.
 

kerplunknet

macrumors 6502
Oct 8, 2006
332
563
I recently purchased the LG 27UK650-W, which is RTINGS #1 recommended monitor that they've tested: https://www.rtings.com/monitor/reviews/best/monitors.

I was getting annoyed with how my LG UltraFine 5K monitors behave when unplugged/plugged.

I used the other monitor for about an hour and then decided that was enough. Returned it.

It made me realize just how premium these UltraFine monitors are. The resolution of 5K compared to 4K is major. With 4K, I could actually see the jagged edges where pixels joined. Also, the backlight bleed was terrible on my model I got.

In summary, unless you can afford Apple's ridiculously-priced 6K monitor, the LG UltraFine 5K is still far and beyond the best monitor available.
 

bpmarkowitz

macrumors newbie
Jun 25, 2010
7
2
I recently "upgraded" from a 5K iMac to a work provided LG Ultrafine 5K.

It will mostly be used with a work provided brand new MacBook Pro and a personal Mac mini.

My question has to do with seeing some scaling issues on the LG. Basically I can see the scaling artifacts on the screen. It's especially noticeable on fonts and on things like menubar that only have a one pixel border. Sometime these lines become blurry. If I shift the window up or a down a bit I can see the blurriness disappear/reappear based on where it is on the screen. I'm running at 2560x1440 so everything should scale nicely. What am I missing - I'm seeing this from both computers.

Welcome any advice or suggestions!

---

UPDATE: was definitely the cable haha. Box has what I guess was just a USB-C cable in the box and also a a true thunderbolt cable? I was using the USB-C cable. Changing to the thunderbolt fixed my issues w/ scaling! Embarrassing but I'll leave my comment in case anyone else has this same issue.
 
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joevt

macrumors 6502a
Jun 21, 2012
825
409
I recently "upgraded" from a 5K iMac to a work provided LG Ultrafine 5K.

It will mostly be used with a work provided brand new MacBook Pro and a personal Mac mini.

My question has to do with seeing some scaling issues on the LG. Basically I can see the scaling artifacts on the screen. It's especially noticeable on fonts and on things like menubar that only have a one pixel border. Sometime these lines become blurry. If I shift the window up or a down a bit I can see the blurriness disappear/reappear based on where it is on the screen. I'm running at 2560x1440 so everything should scale nicely. What am I missing - I'm seeing this from both computers.

Welcome any advice or suggestions!

---

UPDATE: was definitely the cable haha. Box has what I guess was just a USB-C cable in the box and also a a true thunderbolt cable? I was using the USB-C cable. Changing to the thunderbolt fixed my issues w/ scaling! Embarrassing but I'll leave my comment in case anyone else has this same issue.
Mac OS doesn't tell you what resolution is being output to the screen. You are using a 5120x2880 HiDPI frame buffer, but with a USB-C cable, you are only sending a 3840x2160 signal to the display instead of two 2560x2880 signals (via Thunderbolt).

Use SwitchResX to see what the output resolution actually is. In the Current Resolutions tab, double click the current resolution to see the timing info. It shows Pixel Clock, Active, Scan rate, and Scaled to. With the USB-C cable, you probably see Pixel Clock: 533 MHz, Active: 3840x2160, Scale to: 5120x2880. With the Thunderbolt cable, you probably see Pixel Clock: 938.25 MHz, Active: 5120x2160, Scale to: blank.
 

avedis

macrumors newbie
Jan 2, 2015
10
1
Just got the MD5KL-B earlier this month and am really happy with it. Was priced out of the XDR and it's a overkill both in terms of price and functions.

Only bug bear is having to swap cables whenever I want to output from my iPad instead of MacBook Pro.

I read somewhere in this forum there is a TB3 cable from Amazon that has this dual function to connect both TB3 and USB C. Does it exist? Can a kind soul send me the link to it?

Thanks!!!
 

kerplunknet

macrumors 6502
Oct 8, 2006
332
563
Just got the MD5KL-B earlier this month and am really happy with it. Was priced out of the XDR and it's a overkill both in terms of price and functions.

Only bug bear is having to swap cables whenever I want to output from my iPad instead of MacBook Pro.

I read somewhere in this forum there is a TB3 cable from Amazon that has this dual function to connect both TB3 and USB C. Does it exist? Can a kind soul send me the link to it?

Thanks!!!
I haven’t tested it, but you may want to try this: https://www.apple.com/shop/product/MQ4H2AM/A/thunderbolt-3-usb‑c-cable-08-m
 

awu97

macrumors newbie
Feb 23, 2020
2
1
I got two of the Ultrafine 5Ks at work. Is there any way to drive them both from one cable? Maybe drive them at 4K from a dock?
 

Successful Sorcerer

macrumors member
Nov 23, 2019
72
14
I got two of the Ultrafine 5Ks at work. Is there any way to drive them both from one cable? Maybe drive them at 4K from a dock?
It's too much bandwidth so you'll have to use a cable for each at 5K. The description mentions “The display has two Thunderbolt 3 (USB-C) ports, and you can use one to connect to another 4K display.” so one 5K + one 4K or two times 4K should work. I didn't test it though.
 

joevt

macrumors 6502a
Jun 21, 2012
825
409
It's too much bandwidth so you'll have to use a cable for each at 5K. The description mentions “The display has two Thunderbolt 3 (USB-C) ports, and you can use one to connect to another 4K display.” so one 5K + one 4K or two times 4K should work. I didn't test it though.
That description is from the LG UltraFine 4K display. You could connect an LG UltraFine 5K to that to get 4K.

The LG UltraFine 5K only has one Thunderbolt port so it must be at the end of a Thunderbolt chain.
 

oppastopa

macrumors member
May 25, 2019
33
17
So if I'm understanding correctly; a user could purchase the new Ultrafine 4k and by utilizing its extra TB port you could then daisy chain any Ultrafine 5k model to it?
 

Successful Sorcerer

macrumors member
Nov 23, 2019
72
14
That description is from the LG UltraFine 4K display. You could connect an LG UltraFine 5K to that to get 4K.

The LG UltraFine 5K only has one Thunderbolt port so it must be at the end of a Thunderbolt chain.
Ah sorry, you're right! I mixed them up... But why would you choose a lower resolution over two cables?