Looks like this display will work with MBP 2017, but it will not function if you use USBC to USBC cable directly from macbook to the LG USBC port. No display signal is seen by the monitor. That's really really stupid. Why do I need to use an adapter when both ports are USBC? Is this for real?
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LG 4K Monitor (43UD79-B) - FINALLY with USB-C
- Thread starter soamz
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All of these cables are supposed to support it. What I am unsure of is if the monitor supports what I want to do. Seems to be a TON of misinformation about what is and is not doable with this monitor. I'm thinking that the USBC port on the monitor is ONLY for data transfer. I cannot try the display on any other computer as the macbook is the only one I own with a USBC port. LOL.
This does not work:
https://www.amazon.com/gp/product/B01KGTGXQO/ref=oh_aui_detailpage_o04_s00?ie=UTF8&psc=1
This does not work:
https://www.amazon.com/gp/product/B01AS8U8PU/ref=oh_aui_detailpage_o08_s00?ie=UTF8&psc=1
This does not work:
https://www.amazon.com/gp/product/B01AS8U9KE/ref=oh_aui_detailpage_o08_s00?ie=UTF8&psc=1
The mac 'dings' when I plug these in, and it appears to be charging.....not that I need that at all. I need a video signal.
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OK, then if the MBPro "dings" to show charging, then be sure to plug in to your normal adapter before plugging in the USB-C cable to the display. (It's pretty normal to need external power when using an external display)
Another choice, would be to use another connection on the display. There's a DisplayPort connector, so you could try this cable -
https://www.amazon.com/Cable-Matters-DisplayPort-Supporting-Thunderbolt/dp/B01J6DT070/
Another choice, would be to use another connection on the display. There's a DisplayPort connector, so you could try this cable -
https://www.amazon.com/Cable-Matters-DisplayPort-Supporting-Thunderbolt/dp/B01J6DT070/
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Hmm...Well, I'll certainly try the order in which I plug these things in. I don't understand how that could matter, but I'm new to Macs and it's likely that it is smarter than I am. Seems to me, order would not matter, as once it receives ample power, signal would be passed accordingly. No?
Just tried what you suggested. The monitor still says 'no signal'. Does this mean my brand new monitor is defective?! The macbook dings. Has anyone actually used this monitor with the macbook pro 2017 to confirm that it should or should not work?
It works when I use HDMI adapters to the hdmi in on the monitor. but to the USBC port doesnt work.
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I suspect that you want to learn more about "alternate mode" for USB-C, which is how video (DisplayPort) signals are transmitted over USB-C.
https://www.engadget.com/2016/08/21/finding-compatible-usb-c-accessories-is-a-crapshoot/
Read through that article, there's several mentions of alternate mode, and how it doesn't always work, and appears to be quite sensitive to cables (suggesting perhaps that you haven't found a cable that supports that -- or the combination of devices and cables that you have tried, are not yet all talking to each other.
If you read the manual that came with your LG display, you should see (on page 20, I think) the mention of both Power Delivery (provides charging through the USB-C port), and alternate mode (provides displayport video through the USB-C port). The CABLE has to support that mode, too --- not just the hardware. I think you would need to try out a couple more cables --- which, yes, gets a little tiresome, particularly if you don't find a cable that supports that alternate mode.
And, you have a simple solution (that should work), because you also have a DisplayPort connection on the display.
Try a USB-C to DisplayPort cable.
https://www.engadget.com/2016/08/21/finding-compatible-usb-c-accessories-is-a-crapshoot/
Read through that article, there's several mentions of alternate mode, and how it doesn't always work, and appears to be quite sensitive to cables (suggesting perhaps that you haven't found a cable that supports that -- or the combination of devices and cables that you have tried, are not yet all talking to each other.
If you read the manual that came with your LG display, you should see (on page 20, I think) the mention of both Power Delivery (provides charging through the USB-C port), and alternate mode (provides displayport video through the USB-C port). The CABLE has to support that mode, too --- not just the hardware. I think you would need to try out a couple more cables --- which, yes, gets a little tiresome, particularly if you don't find a cable that supports that alternate mode.
And, you have a simple solution (that should work), because you also have a DisplayPort connection on the display.
Try a USB-C to DisplayPort cable.
Very useful info!! I just found something very strange that confirms the port on the monitor IS in fact, functional. I got the USB-C Cable to work on the display for display, BUT....it only works when I plug everything in, and then go to the back of the monitor and unplug it and replug it THERE. Not at the macbook. How wierd is that?? I saw a blurb on the apple support pages where someone with an LG 5k monitor had the same issue and noticed the same thing.
Does this mean anything to anyone?
Look, I can get my monitor to work with HDMI cable to USBC, I have HDMI and an USB adapter that also works, I even have a display port to USBC cable that works too. I have a few options here, I just wanted to get USB C working because it passes sound, data, video....all on one cable.
I tried this again. Couldnt get the cable to work today. After a LOT of screwing around it finally came on.
EIther ALL my cables are bad, or something is seriously unstable with the monitor. What are yalls thoughts?
The computers all respond to the USB port when I use the USBC to USBA adapter...so the data part works on the monitors USBC port.
Does this mean anything? I'm trying to troubleshoot whether or not the USBC port is bad. I dont see reports of it, so Im skeptical its anything but finicky cables, but I can't be sure.
So I did another test with HDMI to USBC cables.....
Windows HDMI -> MOnitor USBC = DOES NOT WORK
Mac USB-C -> Monitor HDMI - Works
Same cable. I tried the same exercise with Displayport to USBC Cable. Same result as above. The USBC to USBC cable only works sometimes and will always work when I unplug and replug it in at the monitor istself.
I mean, is ANYONE actually successfully using this monitor with a macbook pro and a USBC to USBC cable to the monitors USBC port or did everyone just give up and use a different input?
EIther ALL my cables are bad, or something is seriously unstable with the monitor. What are yalls thoughts?
The computers all respond to the USB port when I use the USBC to USBA adapter...so the data part works on the monitors USBC port.
Does this mean anything? I'm trying to troubleshoot whether or not the USBC port is bad. I dont see reports of it, so Im skeptical its anything but finicky cables, but I can't be sure.
So I did another test with HDMI to USBC cables.....
Windows HDMI -> MOnitor USBC = DOES NOT WORK
Mac USB-C -> Monitor HDMI - Works
Same cable. I tried the same exercise with Displayport to USBC Cable. Same result as above. The USBC to USBC cable only works sometimes and will always work when I unplug and replug it in at the monitor istself.
I mean, is ANYONE actually successfully using this monitor with a macbook pro and a USBC to USBC cable to the monitors USBC port or did everyone just give up and use a different input?
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Have you tried a different monitor?
Have you tried using your monitor on a different computer?
Have you tried contacting LG support (or maybe just give up and return the display to perhaps get a replacement display)
Maybe there is some trick to enable the alternate mode for the USB-C to function properly.
Have you tried using your monitor on a different computer?
Have you tried contacting LG support (or maybe just give up and return the display to perhaps get a replacement display)
Maybe there is some trick to enable the alternate mode for the USB-C to function properly.
Eh...LG Support is about 50/50 on whether there is something wrong or not. LOL. It works pretty consistently if you are on a different input and plug in the mac. The monitor immediately responds and asks if you want to go to that input. If you are already on that input, then the monitor usually doesn't recognize something has been plugged in. It's more like a firmware issue to me.
Since you cannot use this monitor with USBC Input AND not have it plugged in (physically impossible, and really a mac design problem) then that input is really not all that useful. So, for now, I'm just plugged into the HDMI. You get 4k and you get 60hz....whatever.
But no...to return a 40lb monitor purchased for well less than currently advertised, nearly 90 days after purchase to a store not all that close on a wild guess and hope it's faulty is not something I want to do. I think the technology just isnt evolved enough to be considered stable or standard yet. It's just too early in its evolution to consider USBC anything more than a fast data transfer novelty.
I think the USB-C would probably work pretty great with a Mac Mini or a iMac...something that has it's own power supply. What I need to do with it...it's just not really designed for that. And with 2 other functional inputs that offer 4k @60hz...why fuss with it.
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Just got my USBC Cable directly from LG! Yeah, it doesnt work at all. What a piece of crap. My last LG monitor crapped an HDMI port about 6 months into ownership. They sure havn't come that far in 8 years.
I had really hoped for one USB-C cable to handle 4k @60hz, the USB hub on the back of the 43UD79-B, and enough juice to power my 13" 2017 MBP, but have not been able to make it happen with a $22 or a $40 cable. In the interest of saving people time (and Amazon the returns) I should note that neither of these would do everything despite their claims and price tags:
[INTEL CERTIFIED] CalDigit Thunderbolt 3 Cable - ACTIVE 40Gbps / 100W Charging / 5A / 20V, 2016-2017 Macbook Pro 2017 iMac Pro (1.0 Meter Cable)
[USB-IF Certified] Cable Matters 20 Gbps Thunderbolt 3 USB-C Cable in Black Supporting 100W Charging 3.3 Feet
I thought for sure one of those would work but tried every arrangement and plugging-in order I could think of to no avail. I still love the display, especially for $500, but it's actually three cables I have to use now because I'm using a USB-C to DisplayPort for video and the USB-C to USB-C one will only deliver the signal from the USB hub on the back of the display (which is just my wired keyboard and the dongle for my Logitech mouse), but not enough power. It will deliver some juice, but not as much as I consume while I'm using it. If anyone knows of a clever way I can get me down to two cables while still running all this stuff, that would be awesome. Unfortunately using Bluetooth instead of the Logitech dongle isn't an option- it's a great mouse when used with that thing but barely works at all via Bluetooth.
[INTEL CERTIFIED] CalDigit Thunderbolt 3 Cable - ACTIVE 40Gbps / 100W Charging / 5A / 20V, 2016-2017 Macbook Pro 2017 iMac Pro (1.0 Meter Cable)
[USB-IF Certified] Cable Matters 20 Gbps Thunderbolt 3 USB-C Cable in Black Supporting 100W Charging 3.3 Feet
I thought for sure one of those would work but tried every arrangement and plugging-in order I could think of to no avail. I still love the display, especially for $500, but it's actually three cables I have to use now because I'm using a USB-C to DisplayPort for video and the USB-C to USB-C one will only deliver the signal from the USB hub on the back of the display (which is just my wired keyboard and the dongle for my Logitech mouse), but not enough power. It will deliver some juice, but not as much as I consume while I'm using it. If anyone knows of a clever way I can get me down to two cables while still running all this stuff, that would be awesome. Unfortunately using Bluetooth instead of the Logitech dongle isn't an option- it's a great mouse when used with that thing but barely works at all via Bluetooth.
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[doublepost=1522347111][/doublepost]I didnt read the whole chain, but i can confirm mine MBP 2017 works just fine with ONE USB-C cable.
It will charge it. The issue is, that if the monitor goes to "sleep" mode, than it stops charging.
[doublepost=1522347152][/doublepost]Oh and its on 60Hz as well
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Which cable did you use? I just got the monitor and tried the USB-C to USB-C supplied by Apple but it doesn't work. I am connecting to the monitor via the HMDI/using a converter.
USB Type C Cable 3.3ft (1m) - Type C to Type C Reversible - USB 3.1 Super Speed Gen 2 - 100w/5a - Metalic Gray with Braided wire - Fast Data Sync & Charging Cord https://www.amazon.com/dp/B071S2FN3T?ref=yo_pop_ma_swf
The link changed on amazon, but look at the description and find a cable that has same specifications
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Hi the URL is for the
USB Type C Cable 3.3ft (1m) - Type A to Type C Reversible - USB 3.0 Super Speed
USB Type C Cable 3.3ft (1m) - Type A to Type C Reversible - USB 3.0 Super Speed
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Read my answer
oops, I guess my reading stopped when I saw the URL. I am surprised the the cable supplied with 2017 Mac doesn't work when this cable (much cheaper) would. I am doubting what you're saying.
Mac cable is “charging only” it has no data transfer. Price has nothing to do with it
Apple cable is charge and data sync so I suppose 'data sync' doesn't include data transfer? Not being facetious with you just wondering why apple sell a ~$30 cable that doesn't do everything a ~$12 cable.
I am a bit confused about this cable situation. Doesn't the monitor already come with some cables? Ordered mine but has not arrived yet. In order to drive this 4K monitor at 60Hz using MBP 2017 13" or 15", what cable do I need actually?
For the issues some of you experience, is it the monitor's problem, Apple's hardware problem and/or Mac OS problem? Does the monitor work well on a non-Apple desktop computer running Linux or Windows?
For the issues some of you experience, is it the monitor's problem, Apple's hardware problem and/or Mac OS problem? Does the monitor work well on a non-Apple desktop computer running Linux or Windows?