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

[ahostmadsen]

1. In my experience with my 4K screen (not the UF series), the rMB is bearable when you're running a perfect scaling of 1x or 2x. In the case of the 4K UF, it's a perfect 2x when you run at 1080p.

That's what I have in mind, running at 1080p. Since most 4K displays are 3840 x 2160, this gives a perfect 2x scaling. Strangely, the LG Ultrafine is 4096-by-2304 according to the spec sheet. Does that mean it shows 1152 (vertical), above 1080p, when running at 2x?

I'm swapping my rMB for a MBP purely because the rMB cannot really handle a 4K screen to an acceptable performance level for my usage. Remember the rMB was never originally intended to be used in this way.

I wonder what usage that is? In my case, I really just work with documents. However, even then with my current external screen (1920 x 1200), animations (e.g., mission control) are choppy. I'm worried it would get worse with a 4K screen.

 

[mctrials23]

That's what I have in mind, running at 1080p. Since most 4K displays are 3840 x 2160, this gives a perfect 2x scaling. Strangely, the LG Ultrafine is 4096-by-2304 according to the spec sheet. Does that mean it shows 1152 (vertical), above 1080p, when running at 2x?

Yep default scaled res is 2048x1152 which is actual 4k (scaled of course) not the slightly lower res that seems to be the standard "4k".

I wonder what usage that is? In my case, I really just work with documents. However, even then with my current external screen (1920 x 1200), animations (e.g., mission control) are choppy. I'm worried it would get worse with a 4K screen.

I can't imagine that it will be good. If that is your monitors default res and its struggling then asking it to push 4k is a big ask. The other thing to consider is that unless you are running it scaled at a not native / nice scaling you are asking even more of the laptop. Driving 2 of these with the current 2016 13" MBP at 1140p scaled is fine but animations are not smooth.

 

[bill-p]

Here's something to consider: I switched from a 1.1GHz rMB 2015 to 1.3GHz rMB 2016, and the performance difference between the 2 when driving a 4K display (Lenovo ThinkVision X1 - 3840 x 2160, not 4096 x 2304) is stark.

The 2016 rMB is just much happier trudging along. I've got about the same amount of animation lag at 4K (2048 x 1152 scaled down) on it as does my rMBP 15" 2012 running at 2560 x 1440, which leads me to believe that there may be limitations built-in to the OS stack to prevent animations from significantly hampering overall system performance. Also I think it may relate to the performance of the GPU being used, as I've noticed that my 2016 rMB has got a much faster GPU than the 2015 model, and the integrated GPU of the 2012 model (2012 has dedicated GPU, which is forced to be on when an external display is connected).

Prior to getting the 2016 model, I was still running the rMB 12" alongside my 15" rMBP, but now I'm highly considering consolidating to just one device. I'm not feeling like I'm losing out much with the 2016 rMB, and my usage involves some light photo editing in Lightroom, some Photoshop, documents, some coding, and occasionally watching 4K cat videos. Probably on the light side there.

 

[ahostmadsen]

Here's something to consider: I switched from a 1.1GHz rMB 2015 to 1.3GHz rMB 2016, and the performance difference between the 2 when driving a 4K display (Lenovo ThinkVision X1 - 3840 x 2160, not 4096 x 2304) is stark.

The 2016 rMB is just much happier trudging along. I've got about the same amount of animation lag at 4K (2048 x 1152 scaled down) on it as does my rMBP 15" 2012 running at 2560 x 1440, which leads me to believe that there may be limitations built-in to the OS stack to prevent animations from significantly hampering overall system performance. Also I think it may relate to the performance of the GPU being used, as I've noticed that my 2016 rMB has got a much faster GPU than the 2015 model, and the integrated GPU of the 2012 model (2012 has dedicated GPU, which is forced to be on when an external display is connected).

Prior to getting the 2016 model, I was still running the rMB 12" alongside my 15" rMBP, but now I'm highly considering consolidating to just one device. I'm not feeling like I'm losing out much with the 2016 rMB, and my usage involves some light photo editing in Lightroom, some Photoshop, documents, some coding, and occasionally watching 4K cat videos. Probably on the light side there.

I have an 1.2GHz 2015 rMB, so perhaps that will be an issue.

I guess I could buy a monitor, and just return it if it doesn't work well. At least with the LG UltraFine 4K I can return it to the Apple store if I'm not happy with the performance. If I buy some other monitor, I will have to ship it back if it doesn't work well with the rMB.

 

[andy9l]

I wonder what usage that is? In my case, I really just work with documents. However, even then with my current external screen (1920 x 1200), animations (e.g., mission control) are choppy. I'm worried it would get worse with a 4K screen.

Very basic usage. Some coding apps on occasion, but it even struggles with Facebook in Safari.

It's just not usable for any length of time, if I'm honest.

Here's something to consider: I switched from a 1.1GHz rMB 2015 to 1.3GHz rMB 2016, and the performance difference between the 2 when driving a 4K display (Lenovo ThinkVision X1 - 3840 x 2160, not 4096 x 2304) is stark.

That's really good to know - thanks for this. I'm still going to go down the MBP route as I've recently started putting together iOS apps, so the MBP should give me slightly better performance over the rMB whilst also running a 4K screen.

Your experience gives me confidence that the base 13" TB MBP will support 4K nicely.

I have an 1.2GHz 2015 rMB, so perhaps that will be an issue.

I guess I could buy a monitor, and just return it if it doesn't work well. At least with the LG UltraFine 4K I can return it to the Apple store if I'm not happy with the performance. If I buy some other monitor, I will have to ship it back if it doesn't work well with the rMB.

Given the rMB models are all so similar in terms of performance for each given year, I would be very surprised if your experience was any different to mine. As you say, though, worth a shot if you buy from Apple (assuming same 14 day return policy applies).

 

[bill-p]

I have an 1.2GHz 2015 rMB, so perhaps that will be an issue.

Yeah, I'm not sure the models differ so little. Specifications do say that the 1.3GHz model has a slightly (10%) faster GPU. Maybe that's the deciding factor?

That's really good to know - thanks for this. I'm still going to go down the MBP route as I've recently started putting together iOS apps, so the MBP should give me slightly better performance over the rMB whilst also running a 4K screen.

Your experience gives me confidence that the base 13" TB MBP will support 4K nicely.

Yeah, if you end up relying on the Simulator in Xcode, then you'll want the fastest thing available. My rMB feels literally twice as slow as my 15" rMBP from 2012 at running the Simulator, and nothing could help that performance. It was slow even when it's running on the internal display.

But on that note, I'm surprised at how fast the 1.3GHz rMB performs in Sierra. It's really up to par with my 15" rMBP in general use. No lag with Facebook or any of the more intensive websites. In fact, I'm running 2 VMs concurrently (1.3GB of RAM allocated to each) for development work, and they're not bogging the machine down at all.

 

[andy9l]

Yeah, if you end up relying on the Simulator in Xcode, then you'll want the fastest thing available. My rMB feels literally twice as slow as my 15" rMBP from 2012 at running the Simulator, and nothing could help that performance. It was slow even when it's running on the internal display.

Indeed, I'm running the simulator on my 1.1GHz rMB at the moment and it's certainly not quick! I'm very new to Xcode, though, so it's not a huge issue at the moment - I'm not doing anything complex at all. For my regular web development work, my little rMB has been surprisingly brilliant.

My problem is I really don't want a 15" MBP, I really don't like their dated and goofy looks (relative to 13"). That leaves me with the power limitations of the 13" models. Probably going to wait out rev 2 of these MBPs anyway, primarily to avoid a rev 1 Apple product.

 

[ahostmadsen]

I could also buy an HDMI 4K display. However, Apple's support documents (https://support.apple.com/en-us/HT206587) state: "MacBook (Retina, 12-inch, Early 2016) and late-2016 MacBook Pro models support 60Hz refresh rates over HDMI when used with a supported HDMI 2.0 display, an HDMI Premium Certified cable, and a supported USB-C to HDMI 2.0 adapter."

Thus, I would conclude that my 2015 rMB does NOT support 60Hz over HDMI. However, it should support 60 Hz for the LG 4K display. The same document states: "With macOS Sierra, MacBook (Retina, 12-inch, Early 2015) and later supports 4K (3840x2160) displays at 60Hz operation over DisplayPort"

So, my rMB should support 60Hz over displayport. However, I don't believe there are any USB-C to Displayport adapter. And anyway, does any modern display have displayport input, in addition to HDMI? Thus, a USB-C display is needed (and presumably supports 60 Hz -- perhaps the computer sees it as displayport?).

 

[andy9l]

I could also buy an HDMI 4K display. However, Apple's support documents (https://support.apple.com/en-us/HT206587) state: "MacBook (Retina, 12-inch, Early 2016) and late-2016 MacBook Pro models support 60Hz refresh rates over HDMI when used with a supported HDMI 2.0 display, an HDMI Premium Certified cable, and a supported USB-C to HDMI 2.0 adapter."

Thus, I would conclude that my 2015 rMB does NOT support 60Hz over HDMI. However, it should support 60 Hz for the LG 4K display. The same document states: "With macOS Sierra, MacBook (Retina, 12-inch, Early 2015) and later supports 4K (3840x2160) displays at 60Hz operation over DisplayPort"

So, my rMB should support 60Hz over displayport. However, I don't believe there are any USB-C to Displayport adapter. And anyway, does any modern display have displayport input, in addition to HDMI? Thus, a USB-C display is needed (and presumably supports 60 Hz -- perhaps the computer sees it as displayport?).

In short, the 2015 rMB supports 4K @60Hz using USB-C "alt-mode". In theory, any 4K USB-C capable monitor will run at 60Hz with your rMB. Mine certainly works with the LG 27UD88.

Most modern monitors will offer DisplayPort 1.2+ and HDMI 2.0. An increasing number now offer USB-C input.

 

[ahostmadsen]

In short, the 2015 rMB supports 4K @60Hz using USB-C "alt-mode". In theory, any 4K USB-C capable monitor will run at 60Hz with your rMB. Mine certainly works with the LG 27UD88.

Most modern monitors will offer DisplayPort 1.2+ and HDMI 2.0. An increasing number now offer USB-C input.

Yes, you're right, I checked the tech specs, they do have displayport 1.2. But using the display port seems tricky. There are indeed some USB-C to display port cables. But I would also want to charge the computer. So, I would need a USB-C hub. Or a USB-C hub with a displaport. And who knows if that combination would actually work at 60Hz. And the combination would cost more than a USB-C monitor.

Conclusion: the only option is a USB-C monitor. I'm thinking either the LG UltraFine 4K, or the HP Envy 27" monitor. But I think the HP monitor does not even have a single USB-C output port, so to connect anything to the rMB, like a disk, I would also need a hub.

 

[bill-p]

Have you looked at the Lenovo ThinkVision X1? That's what I have, and it works well as a display, a hub, and a webcam (I rarely use the webcam so it doesn't matter) just with a single USB-C connection.

It's also a nice bonus that it charges the computer while I have it plugged in.

 

[ahostmadsen]

Have you looked at the Lenovo ThinkVision X1? That's what I have, and it works well as a display, a hub, and a webcam (I rarely use the webcam so it doesn't matter) just with a single USB-C connection.

It's also a nice bonus that it charges the computer while I have it plugged in.

Yes, that is a good option. But it is somewhat more expensive than the LG/Apple or HP. The final alternative is the LG 27UD88-W, but that doesn't seem in stock anywhere.

 

[andy9l]

Yes, that is a good option. But it is somewhat more expensive than the LG/Apple or HP. The final alternative is the LG 27UD88-W, but that doesn't seem in stock anywhere.

That's what I went for back in November last year. Love it, but it does appear to be hard to find now.

 

[bill-p]

Yes, that is a good option. But it is somewhat more expensive than the LG/Apple or HP. The final alternative is the LG 27UD88-W, but that doesn't seem in stock anywhere.

You do pay for convenience.

The HP Envy 27 doesn't have a hub, so you need to connect the display to a hub that you will then connect to your MacBook. That hub alone can cost anywhere from $50 - $100. Not to mention compatibility issues. Unless all you'll be plugging into your MacBook at home is the screen, that is. Then yeah, in which case, it's a decent value.

The LG 22MD4K has some extra USB-C ports, but... they are all running at USB 2.0, and yet they are still USB-C, so you need to adapt those USB-C ports to regular USB if you have any device that still relies on regular USB-C to run. The added extra cost of the adapters can go up to $100 easily. Not to mention you're looking at a 21.5" screen.

The 27UD88-W costs more than the Lenovo right now if you'd look at pricing, and that's on top of rarity. A part of the rarity is due to the recently discussed problems with the displays being in close proximity to network routers.

I don't want to defend my purchase, but it seems clear how the market is segmented. You still end up having to pay more one way or another.

If costs were the ultimate factor, I'd also argue that you can just do USB-C -> Hub w/ DisplayPort -> one of those cheaper 4K displays from Asus or Samsung, and that'd be a better value proposition than going with the HP Envy since it's cheaper even after you have factored in the extra hub.

 

[ahostmadsen]

The LG 22MD4K has some extra USB-C ports, but... they are all running at USB 2.0, and yet they are still USB-C, so you need to adapt those USB-C ports to regular USB if you have any device that still relies on regular USB-C to run. The added extra cost of the adapters can go up to $100 easily. Not to mention you're looking at a 21.5" screen.

So, you're saying that the extra USB-C ports on the LG/Apple display cannot be used as USB-C ports? That would be a strange design choice.

 

[bill-p]

So, you're saying that the extra USB-C ports on the LG/Apple display cannot be used as USB-C ports? That would be a strange design choice.

It's a bit more complicated than that, but I guess the full answer goes as follow:

USB-C is a type of port, preceded by the more popular USB-A and the somewhat less popular USB-B that you see mostly in printers. As such, it's really just a type of port in nature. It's technically correct to say that as long as you have a USB-C port, then they can be used as USB-C ports.

I alluded specifically to the ports' speed, though, to be more precise, because that's where we have the problem of usability.

When you connect to a 4K display to the MacBook 12" and run it at 4K 60Hz, the computer uses up its data connection lanes, and you end up with lower USB port speed. This is a universal "problem", and it happens regardless of display. Here's someone else who's running into the same "problem": https://9to5mac.com/2016/06/04/lg-27ud88-w-usb-c-4k-monitor-macbook-review/

"USB 3 utilizes 4 lanes in pairs (2up/2down), and the DisplayPort connection can assume operation of some or all of these lanes. The MacBook connection, as it turns out, utilizes all four lanes, causing data connectivity to fall back to USB 2.0 speeds."

So with the MacBook 12", those USB-C ports are as good as USB 2.0 (480Mbits/sec), and in fact, Apple themselves know about this, so they advertise just that much in their listing of the LG display: http://www.apple.com/shop/product/HKMY2VC/A/lg-ultrafine-4k-display

"A single USB-C cable (included) provides up to 60W of charging power to your MacBook with USB-C port or MacBook Pro with Thunderbolt 3 (USB-C) ports. And three downstream USB-C ports (480 Mbps) offer additional connectivity and power to compatible devices and accessories."

Notice they wrote "480Mbps" there.

So the ports are running at USB 2.0 speed. They are still USB-C ports, but you're not getting the full speed advantage of USB-C with them when the display is in use, which kinda defeats the purpose. So it's not like you can't use the ports "as USB-C ports", you're just not getting the most out of them to even warrant having them in USB-C form.

 

[ahostmadsen]

It's a bit more complicated than that, but I guess the full answer goes as follow:

USB-C is a type of port, preceded by the more popular USB-A and the somewhat less popular USB-B that you see mostly in printers. As such, it's really just a type of port in nature. It's technically correct to say that as long as you have a USB-C port, then they can be used as USB-C ports.

I alluded specifically to the ports' speed, though, to be more precise, because that's where we have the problem of usability.

When you connect to a 4K display to the MacBook 12" and run it at 4K 60Hz, the computer uses up its data connection lanes, and you end up with lower USB port speed. This is a universal "problem", and it happens regardless of display. Here's someone else who's running into the same "problem": https://9to5mac.com/2016/06/04/lg-27ud88-w-usb-c-4k-monitor-macbook-review/

"USB 3 utilizes 4 lanes in pairs (2up/2down), and the DisplayPort connection can assume operation of some or all of these lanes. The MacBook connection, as it turns out, utilizes all four lanes, causing data connectivity to fall back to USB 2.0 speeds."

So with the MacBook 12", those USB-C ports are as good as USB 2.0 (480Mbits/sec), and in fact, Apple themselves know about this, so they advertise just that much in their listing of the LG display: http://www.apple.com/shop/product/HKMY2VC/A/lg-ultrafine-4k-display

"A single USB-C cable (included) provides up to 60W of charging power to your MacBook with USB-C port or MacBook Pro with Thunderbolt 3 (USB-C) ports. And three downstream USB-C ports (480 Mbps) offer additional connectivity and power to compatible devices and accessories."

Notice they wrote "480Mbps" there.

So the ports are running at USB 2.0 speed. They are still USB-C ports, but you're not getting the full speed advantage of USB-C with them when the display is in use, which kinda defeats the purpose. So it's not like you can't use the ports "as USB-C ports", you're just not getting the most out of them to even warrant having them in USB-C form.

Thanks for the detailed reply. I interpret it as follows:

1) The USB-C port on the MacBook cannot really support high speed USB-C when running a monitor at 4K 60 Hz, no matter what monitor.
2) The LG/Apple has USB-C output ports, but they cannot be fully utilized as USB-C ports due to the above speed limitations.
3) The Levono has a USB-A hub (I think), which is more relevant at the possible speeds.

 

[ahostmadsen]

I ended up ordering the HP ENVY 27" display: it's the cheapest of the bunch, about same as the LG/Apple 4K display, but I think the larger size is preferable. I rarely connect anything to my rMB apart from a display. The only thing is my camera a couple of times a month. Irritating I will have to disconnect my computer from the screen, but not a deal breaker.

HP has free return shipping, so if it doesn't work well with my rMB, nothing is lost.

 

[andy9l]

I ended up ordering the HP ENVY 27" display: it's the cheapest of the bunch, about same as the LG/Apple 4K display, but I think the larger size is preferable. I rarely connect anything to my rMB apart from a display. The only thing is my camera a couple of times a month. Irritating I will have to disconnect my computer from the screen, but not a deal breaker.

HP has free return shipping, so if it doesn't work well with my rMB, nothing is lost.

I imagine it'll work well at 1080p @2x (default "retina" scaling), but it looks so goofy to have 1080p on a 27" screen. When you scale it to look like 1440p, performance may start to suffer.

Good luck!

 

[ahostmadsen]

I imagine it'll work well at 1080p @2x (default "retina" scaling), but it looks so goofy to have 1080p on a 27" screen. When you scale it to look like 1440p, performance may start to suffer.

Right now I have a 26" 1920x1200 external screen. My expectation is that at 1080p @2x, everything on the 27" screen will be about the same size, but with twice the resolution. That should be OK. If I really don't like it, I will get the LG/Apple 4K screen instead.

 

[andy9l]

Right now I have a 26" 1920x1200 external screen. My expectation is that at 1080p @2x, everything on the 27" screen will be about the same size, but with twice the resolution. That should be OK. If I really don't like it, I will get the LG/Apple 4K screen instead.

Ah right, in that case 1080p @2x should work for you!

And yes, everything will technically be twice as sharp.

 

[ahostmadsen]

I went to an Apple store to buy the LG 4K Ultrafine display (I decided to buy both the HP Envy 27" and the LG/Apple display and return the one I like least). But the sales people claimed both the 4K and 5K displays had been discontinued from today, until the WiFi problems have been fixed. They were quite adamant until I could show them that if I ordered online, it said I could pick it up from the store today. Then they went to speak to a manager, and located a display for me.

Perhaps the salespeople were just confused about the 5K or 4K displays? Or did they have advance knowledge of discontinuation of the 4K display.
[doublepost=1486946702][/doublepost]Well, I got the LG display, but it does not really work with my rMB. When I use it in non-clamshell mode, the display on the rMB itself flickers like hell. Anyone else experience that?

 

[ahostmadsen]

Well, it doesn't flicker anymore.

 

[bill-p]

Yeah, I think it's something in 10.12.3. I never experienced anything like that in 10.12.2.

In fact, I was able to plug my MacBook in clamshell mode into the display via USB-C in 10.12.2, and it'd wake the computer up, display things, and allow me to log in and go about my business as per usual. 10.12.3 is somehow messing with that now.

 

[andy9l]

Had no issues still with my 27UD88.

The employees don't have any advanced knowledge - just got it wrong! Don't worry.