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glindon

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Jun 9, 2014
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Today I purchased the LG 27" 27ud88 4k display with usb-c port. It retails for $699. I know a few of you were wondering about using a 4k display with the rMB so here goes...

http://www.amazon.com/gp/product/B0...rd_t=36701&pf_rd_p=2437869742&pf_rd_i=desktop

In the box

The box includes the monitor (of course), base and stand, 1 USB-C to USB-C cable, 1 HDMI cable, 1 DisplayPort to DisplayPort cable (full size, not miniDP), ~140W power brick and cord (in a word, it's huge), and a USB-C to USB A male cable. This is nice if you have a newer USB-C hard drive and can plug it directly into the monitor. I assume you could use it to charge a phone as one of the ports can be configured for quick charging, although you lose the ability to transfer data from that port if you select that option. I have an iPhone so I can't test the port for quick charging.

Look and Finish

The display is minimalist and goes quite well with my Apple gear. It features a curved base that has a nice silver finish. The color is close to the aluminum on my MacBook. The display itself has a very thin silver frame surrounding the screen. There isn't much black bezel to speak of. A very small LG logo sits at the bottom of the display in the center. An tiny energy star sticker is in the lower right corner. I tore it off. Around back the monitor is entirely white glossy plastic as is the stand. As with all glossy plastic, it attracts fingerprints so keep that in mind if your desk is facing away from a wall.

Specs and Ports

On the back of the monitor there is 1 USB-C port, 2 type A USB 3 ports, 1 USB service port (for firmware updates only), 2 HDMI ports, and a headphone jack. I do wish they placed the USB ports more to the bottom of the monitor as they are quite high. The monitor has a height adjustment and at the highest setting the ports are about 14 inches from the desk surface. This is troubling because my external SSD came with a 12 inch cable. As of now I have it resting on its edge as the cable isn't long enough for it to lay flat on my desk. When the monitor is completely lowered the cable still isn't long enough.

Display wise it's a 27" IPS 4k with 99% sRGB coverage. It has a 350 nit rating and 5ms response time. I don't have the equipment to test these claims from LG so you'll have to take their word for it. The display is semi glossy and I didn't notice any annoying glare from the lights on my fan overhead. Colors and contrast seemed great out of the box. LG says they calibrate the monitor at the factory and I believe them. I didn't notice any large differences in color compared to the MacBook's own display. Having used many third party monitors with my Macs over the years, this is the first time I wasn't disappointed with the colors and spent hours trying to get the colors and text to look as good as they did on my Mac. The brightness was higher than what my Mac was at, given the ambient lighting.

In Use

In addition to the standard tilt, the monitor has a generous height adjustment and you can also turn the display 90º. I tried the monitor this way for about 30 minutes before my neck started hurt from craning to look towards the top of the display. Situated in this manner the display is 2 feet tall. Using the monitor like this unpractical in my opinion but it's nice to have the option.

Controlling the display settings is a breeze. A single joystick button sits underneath the monitor in the center and can be operated without having to look at it and can be found in the dark. Holding down the button turns the display on an off.

USB-C. One port to rule them all? Also the 60hz question.

The monitor came with the necessary USC-C to USB-C cable. Plug one end into the monitor and the other into your MacBook and you're good to go. This is the best part of this monitor and the future of all MacBooks I'm certain. This one cable carries the DisplayPort signal to the monitor, USB 3 to the two ports on the back of the monitor, and also supplies power to charge the MacBook. I can't tell you how elegant and Apple-like this solution is. The only thing missing is ethernet—and Thunderbolt. Ethernet can be added with a USB 3 to ethernet adapter from the back of the monitor if it's something you really need. Thunderbolt can't be added of course but in my opinion having everything else go through the USB-C port kinda negates the need for Thunderbolt. If you rely on having Thunderbolt accessories, then the MacBook was probably never the machine for you to begin with. Both of the Thunderbolt external hard drives that I own also have USB 3 ports so I haven't had to buy new gear. One thing to keep in mind; if you are using the MacBook in clamshell mode, make sure you are in close range to your router. The MacBook isn't as RF friendly due to it being an all metal design. On older Macs the antennas were by the glowing Apple logo and also around the black plastic strip at the hinge. The MacBook has neither and the antennas are solely located on the front of the display. Putting the MacBook in clamshell mode literally blocks the "window" and signal strength does drop a bit. Surprisingly the built in speakers were still rather clear and loud when played while in clamshell mode. The MacBook didn't run any warmer driving this monitor than it did running only the native display. The MacBook ran fine driving both displays at the same time. I ended up keeping it in clamshell mode, connected to the Magic Keyboard and Magic Trackpad 2.

Display Preferences only gives the option to run the monitor at 1080p retina resolution, as well as some lower resolutions which weren't retina. I didn't bother trying any of the lower resolutions as they're pretty much pointless. Using the 1080p retina resolution—while not ideal for this size of monitor—was not that bad at all due to the text being sharp and legible. I installed Retina DisplayMenu (RDM) utility and was able to set the monitor to native 4k resolution and while usable, the text is incredibly small as is all the UI elements. I'm going to do a little more testing and see how the monitor works with scaled 2560x1440 and will report back.

Apple lists the MacBook as only supporting 30hz at 4k resolutions, while Intel lists the Core M as supporting 60hz. So which is it? Unfortunately the MacBook only does 30hz when plugged into the monitor. For some this may be a deal breaker. For me personally, the lack of 60hz—while a bummer—isn't enough of a hinderance to not enjoy using this monitor. Most all movies are encoded in 24 or 30 fps and they played as smooth as they did on the MacBook's native display. Most of the time I'm using my Mac to write or to code. The only time I really notice the 30hz is when scrolling down a webpage or using Expose. These are brief interactions so the frame rate doesn't bother me as much as I thought it would. I know this will probably drive some people crazy. The monitor itself does support 60hz through the USB-C port, and I'm sure that within a year or two the MacBook will be powerful enough to support this monitor at 60hz.

To buy or not to buy

I was waiting for reviews to come out on this monitor before buying. Seeing it was for sale at my nearby Fry's, I took a short drive and bought it knowing that I could just return it if I hated it. I'm going to use it for the next week or so before making a final decision as to whether I'll return it or not. Right now I'm leaning towards keeping it.

Let me know if you have any other questions. There's some other stuff the monitor can do such as PIP and also simultaneous inputs but I haven't tested any of that out yet.
 
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Great write up! I'm sticking to a wQHD until 60hz 4K. I love the fact USB-C monitors can power the MacBook.
 
Fry's had it for $699 and I price matched it to Amazon at $680. I decided to keep it, mostly because the image quality is great and because next years MacBook should support 60hz. I really tossed around getting a 27" iMac but I don't need the power and I really don't want to manage 2 computers. It's just way too convenient to be able to plug everything in all at once with a single cable.
 
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Fry's had it for $699 and I price matched it to Amazon at $680. I decided to keep it, mostly because the image quality is great and because next years MacBook should support 60hz. I really tossed around getting a 27" iMac but I don't need the power and I really don't want to manage 2 computers. It's just way too convenient to be able to plug everything in all at once with a single cable.

Cool. I've been eyeballing a few 4K monitors, as well as the 2016 rMB. My main daily driver is a Late 2014 Mac mini, which has effectively the same 4K support as the 2016 rMB, i.e. not great. My other computer is the Late 2013 Mac Pro, and I'd have to see how/if the LG can support it via MST.
 
What a gorgeous monitor! But I am waiting on 4K monitors till the prices come down
 
Am unsure if this is a good purchase for the 2016 macbook or not? is there a general yea or nay on 4K monitors for the 2015 & 2016 MacBooks?

i was thinking about getting a ThinkVision x1 for a 2016 macbook m7 so i am very interested in others experience.

Generally i only use my laptop for reading, browsing, office stuff, scripting and seeping through data sets and all my heavy processing is preformed by an elastic computing cloud, so gennerally i am very happy for the lightweight macbook, but a monitor like ThinkVision x1 would also provide a HD webcam which is the only thing i am missing - besides full 4K support for the occasional 4k tv shows.
 
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Am unsure if this is a good purchase for the 2016 macbook or not? is there a general yea or nay on 4K monitors for the 2015 & 2016 MacBooks?

i was thinking about getting a ThinkVision x1 for a 2016 macbook m7 so i am very interested in others experience.

Generally i only use my laptop for reading, browsing, office stuff, scripting and seeping through data sets and all my heavy processing is preformed by an elastic computing cloud, so gennerally i am very happy for the lightweight macbook, but a monitor like ThinkVision x1 would also provide a HD webcam which is the only thing i am missing - besides full 4K support for the occasional 4k tv shows.

The big downside is the 30hz refresh rate as addressed in this review. Most people won't find this acceptable, but it's something you'd probably have to try for yourself.
 
The big downside is the 30hz refresh rate as addressed in this review. Most people won't find this acceptable, but it's something you'd probably have to try for yourself.

30hz didn't bother as much as I thought I would. I will say that 4K monitors at this size are a mixed bag. You either run them at native resolution and text is extremely tiny or you run then in retina resolution and text is rather large. The perfect size would be 21" like in the retina iMac but sadly no one sells one. Dell sells a 24" for under $400 but the panel isn't as good as the LG I bought. To get normal sized text at native resolution you'd need about a 36" behemoth.
 
30hz didn't bother as much as I thought I would. I will say that 4K monitors at this size are a mixed bag. You either run them at native resolution and text is extremely tiny or you run then in retina resolution and text is rather large. The perfect size would be 21" like in the retina iMac but sadly no one sells one. Dell sells a 24" for under $400 but the panel isn't as good as the LG I bought. To get normal sized text at native resolution you'd need about a 36" behemoth.

I often end up with my work computer running at 30hz on my 4K monitor when an update resets my graphics driver, and it's passable for a bit, but it's definitely much more comfortable in the long term with a higher refresh rate.

I believe I recall that the MBP's can do scaling when connected to 4K displays - at the cost of some performance. I wonder if the MB is just not given that option because it requires considerable graphics power that they don't yet have?

I have the larger 27" Dell monitor and it's a very nice screen in an age of very good screens. I would have no qualms about buying one of those, but for the MacBook, I think the sweet-spot is currently the 34" ultra-wide monitors if you have the space. Nearly 4K resolution, but able to be driven at 60hz, and a large enough screen to make the small-ish content legible.
 
Don't have MBR nor LG 27" 27ud88 4k, but wonder if anybody tried getting 60Hz to work with SwitchResX?
http://www.madrau.com/srx_howtouseit/srx_howtouseit/srx_your_mac.html
http://www.madrau.com/srx_howtouseit/srx_howtouseit/srx_timings.html

intel does indeed state 4K @60hz is possible with a variety of interfaces in their specifications "link to intel"

4K Support Yes, at 60Hz
Max Resolution (Intel® WiDi)‡ 1080p
Max Resolution (HDMI 1.4)‡ 4096@2304@24Hz
Max Resolution (DP)‡ 3840x2160@60Hz
Max Resolution (eDP - Integrated Flat Panel)‡ 3840x2160@60Hz

SwitchResX looks very interesting - it would be indeed be cool if someone tested if it could force 4K @60hz and then monitored the rMB for a couple of days..


in hindsight some of the old rumors seems a bit laughable even though it might be sort of a write up error " Previously leaked Intel slides reveal that the Y series Skylake chip, which is the fanless architecture used on the MacBook, could deliver up to 17% faster CPU performance and 41% faster GPU performance. Intel revealed that the integrated Gen9 graphics of the Skylake processor can drive up to three 4K displays at 60 frames per second. "
 
intel does indeed state 4K @60hz is possible with a variety of interfaces in their specifications "link to intel"

4K Support Yes, at 60Hz
Max Resolution (Intel® WiDi)‡ 1080p
Max Resolution (HDMI 1.4)‡ 4096@2304@24Hz
Max Resolution (DP)‡ 3840x2160@60Hz
Max Resolution (eDP - Integrated Flat Panel)‡ 3840x2160@60Hz

SwitchResX looks very interesting - it would be indeed be cool if someone tested if it could force 4K @60hz and then monitored the rMB for a couple of days..


in hindsight some of the old rumors seems a bit laughable even though it might be sort of a write up error " Previously leaked Intel slides reveal that the Y series Skylake chip, which is the fanless architecture used on the MacBook, could deliver up to 17% faster CPU performance and 41% faster GPU performance. Intel revealed that the integrated Gen9 graphics of the Skylake processor can drive up to three 4K displays at 60 frames per second. "

The limitation in the Macbook is not in the CPU, which is described accurately, but in the implementation that Apple has chosen in the Macbook. There are only 4 available lanes for combined USB 3 and display out. 4k/60hz would have occupied all 4 lanes, leaving none available for usb 3. So Apple splits it, giving 2 lanes for the display (enough for 4k/30hz) and 2 for usb 3.
 
Apparently you can force at least 50Hz by using SwitchResX (on the 2015 Model). Would be nice if someone checked if it's possible to force even more using the 2016 model.

https://twitter.com/notasausage/status/606911186010054658

I'm currently running a Dell P2415Q at 1080p HiDPI @ 52Hz on a Early 2014 MBPr 13" and you really can't tell the difference from 60Hz.

If the 2016 Macbook 12" can be forced to 50Hz it would be "good enough" for me.
 
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50hz is fine - that's what I use on my Surface Pro at work connected to my Dell p2715q. You won't get more than that on the 2016 because again, the limitation is in the USB-c port, not the cpu or GPU.
 
This may sound like a stupid question but will forcing the Macbook to 4k 50Hz result in lower Performance?

The thing is: 50Hz are a bit useless if the 4k Videos or fullscreen websites start to lag because even though the Macbook is forced via Software, it can't handle with the hardware.

How will this affect the number of usb 3 Ports via a Dock/usb C Hub?

Will this also work over HDMI?
 
It won't result in slower performance. If the MacBook can render a animation at only 30fps then it's going to look the same on 30Hz and 50Hz.

Honestly the only thing that bothers me about 30Hz is how the cursor stutters, and at 50Hz it's smooth.

@glindon any chance you would be up for trying to force this display to 50Hz with SwitchresX over USB-C?
 

There's even a screenshot of a 2016 Macbook 12" running at 1080p Retina @ 60Hz over Displayport.

HCUB6QN.png
 
My brain is hurting thinking about how this even works. I understood the bandwidth on the USB 3.0 Gen 1 bus does not support the throughput required for 4K @ 60Hz?

This has nothing to do with USB speeds. I don't know what they are doing, but it's likely that they are somehow hacking the system to force the displayport connection to use all 4 available lanes in the usb-c connector, rather than the 2 that Apple allocates. If so, that would mean usb 2 speeds for any connected peripherals.
 
This has nothing to do with USB speeds. I don't know what they are doing, but it's likely that they are somehow hacking the system to force the displayport connection to use all 4 available lanes in the usb-c connector, rather than the 2 that Apple allocates. If so, that would mean usb 2 speeds for any connected peripherals.

Ah, now that makes sense. I always have bad luck/instability with I turn off SIP, so this hack doesn't seem like something I'd be keen to try. However, if there was a hardware hack (like a dock, adapter or dongle), that would be more interesting to me.
 
So, I have tried discovering this on my own but I just can't seem to find a definitive answer.

Is it possible to run lower resolution monitors at 60hz?
 
This has nothing to do with USB speeds. I don't know what they are doing, but it's likely that they are somehow hacking the system to force the displayport connection to use all 4 available lanes in the usb-c connector, rather than the 2 that Apple allocates. If so, that would mean usb 2 speeds for any connected peripherals.

The patch only patches the method _CheckTimingWithRange so it always returns good/true response, hence you get to choose all available resolutions and refresh rates. If this then makes the Macbook use all four lanes, it can only mean that Mac OS supports using four lanes on the Macbook, but Apple is disabling it.

Anyway, I hope there will be some more confirmation that this works over USB-C and that the USB ports are functional (even at 2.0).
 
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