Menu
Nov 11, 2016 - How to connect a second external display to a MacBook, MacBook Air. Or in 'extended desktop/dual display mode' -- where each display is.
Active1 year ago
I'm trying to hook up dual monitors (Samsung CF390) to my MacBook Pro, but when I do, I only have the desktop image projecting on both screens. When I go into Settings > Display, the 'Arrangement' option isn't available.
I have both monitors' HDMI cables running through 1 USB-C to HDMI adapter. (The adapter has two ports.)
Is the solution to this problem having two adapters? My thinking is even though the adapter has 2 ports, the MacBook hardware or software can't Fully make use of both displays.
What can I change to get three total displays working on macOS High Sierra (10.13.x)?
bmike♦169k4646 gold badges308308 silver badges664664 bronze badges
GrayGray
1 Answer
I have the same issue. As far as I can tell, it's an issue with High Sierra. and DisplayLink that's not fully resolvable other than through downgrade to an earlier version of the OS. Here's the notice from DisplayLink:
DisplayLink has worked for many months to maintain support for its users during the transition from macOS High Sierra to Mojave. While functionality such as Ethernet and audio or charging, where implemented, is unaffected on all releases, display connectivity has been limited on macOS releases from 10.13.4 through 10.13.6.
Developers/users with access to Apple’s fifth developer preview of 10.14 Mojave, released on 30th July, will see full support has now been restored for multiple extended DisplayLink displays where DisplayLink driver v4.3 beta 5 is installed. We are doing wide scale testing of v4.3 beta against this preview and will release a new driver upon general availability of 10.14.
Users of 10.13.4-10.13.6 should also use v4.3 beta 5 as it contains a workaround to enable one extended USB display (720p or 1080p). An FAQ details how to enable Apple AirPlay with DisplayLink display for extend or mirror mode.
Their workaround kind of works, but it messes up the resolution of the primary monitor and causes periodic flickering. Here's a direct link to that workaround: support.displaylink.com/knowledgebase/articles/1854724.
After updating to MacOS Mojave version 10.14 Beta (18A384a) and DisplayLink v4.3 beta, I can confirm that the 'Arrangement' tab comes back and that my laptop recognizes both external monitors and the laptop display at the same time. However, both monitors are always black. The cursor still moves across all three screens, but that's about it. In other words, functionally multiple monitor capability is still broken as of the above MacOS version.
If you select mirror mode, then select 'Gather Windows,' and then change the external monitors' 'Optimize for:' option to 'Built-in Retina Display,' you can get mirror mode to work nearly properly (there's occasional minor flicker), but there's still no solution for other modes (e.g. where each display is independently able to host windows).
ZaxRZaxR
You must log in to answer this question.
Not the answer you're looking for? Browse other questions tagged macbookdisplaythunderbolt .
Active2 months ago
I looked for 20 minutes for a post similar to mines, and couldn't find one. Which is interesting to me, because I don't understand why people want to use the display to HDMI instead of using thunderbolt USB-c port natively instead. Before I get to this...I shall ask my question.
I plan on buying a MacBook Pro-2018 15 inch for my home-based business. I need to connect 3 monitors to this laptop. I understand the 15 inch MacBook Pro comes with 4 thunderbolts 3 ports. I plan to buy 3 24-27 inch monitors that are 4k display. Also, I understand that the charger for this laptop uses a Thunderbolt 3 port, which leaves me with 3 left. Will connecting 3 monitors that have Thunderbolt 3 ports leave me with performance issues? Will the refresh rate lower?
Finally, why do I see a lot of post with people using old 2.0 display port to HDMI; why they can use Thunderbolt 3 port natively?
Joseph BourneJoseph Bourne
6 Answers
I currently use 3 4k displays (Dell P2715Q) on a MacBook Pro 15' 2017 (GPU: Radeon Pro 560 4096 MB).
Two monitors are connected to the right side ports/bus and the third one (plus a dock for charging/USB/etc) are connected to left side ports/bus. The monitors are arranged in a 'H-shape' with two monitors flipped 90 degrees.
I've had this setup for about 6 months now and while it is usable, I do face some issues from time to time, always after waking up the monitors after sleeping overnight:
- The orientation (90 degree rotation setting) tends to get messed up in two of the three monitors and I have to waste 1-2 minutes fixing it on
System Preferences > Displays
. The cause for this likely a software/compatibility issue on macOS and I have had this on a two monitor setup as well. - Every now and then the ONE of the monitors connected to the right bus fails and I can't make BOTH work again without a system reboot. By repeatedly disconnecting/reconnecting the mDP cables I can get EITHER of them to work, but often not BOTH simultaneously, which is pretty annoying. I feel like this is a hardware issue, perhaps GPU memory issue, but more likely something to do with the Thunderbolt bus bandwidth as it always happens to the bus that has 2 monitors attached to it and never to the one that has only a single monitor attached to.
TL;DR: It is possible but be prepared for some minor issues and eventual monitor 'loss' followed by a system reboot.
Gustavo BezerraGustavo Bezerra
For anyone trying to do this using a dock that has multiple display outputs, the MacBook Pro 2018 only has two thunderbolt busses, but 4 ports (2 ports per bus), as a result, if you try to connect three external monitors, you will need to use different sides of the device.
If you try to connect all three monitors into two ports on one side, it won't work.
EckstersEcksters
From the MacBook Pro Technical Specs page:
Simultaneously supports full native resolution on the built-in display at millions of colors and:
Up to two displays with 5120-by-2880 resolution at 60Hz at over a billion colors.
Up to four displays with 4096-by-2304 resolution at 60Hz at over a billion colors.
As per Apple, you should be fine with upto 4 4K display.
Nimesh NeemaNimesh Neema25.2k99 gold badges6363 silver badges9999 bronze badges
Yes, you can connect 3 x 4k-monitors to the 2018 15' MacBook Pro - and yes, you can use USB-C to DisplayPort cables to connect the monitors.
Doing it this way will take up 3 of the 4 ports, leaving one available for charging, as you describe.
You will not suffer from lower refresh rates, nor 'performance issues' as such that are specifically related to connecting the 3 displays in this manner.
You'll often see people using docks or other adapters to allow connecting multiple displays to a single Thunderbolt 3 port - leaving more ports available for other things, and simplifying connecting the displays when docking/undocking. In this case, the docks often offer HDMI ports instead of DisplayPort.
jksoegaardjksoegaard26k11 gold badge3333 silver badges6363 bronze badges
Reading this guide may help you:
It helped me a lot, although the guide is from a dockstation manufacturer, it's somehow neutral, and addresses in a practical way the different scenarios that we can face when we want to work with multiple screens in our MacBook Pro, either using a single cable solution or with the help of a dock station.
Mine is a 15' MacBook Pro w/TouchBar and I have three 4K connected screens, two using a single port each, and the third is using a tethered dock that even provides power to charge my laptop.
Marcelo EspinosaMarcelo Espinosa
I just installed a driver from https://www.displaylink.com and plugged this recent Macbook Pro into a Dell D6000 docking station via a single USB C (not Thunderbolt) cable that my colleague is using for his Dell. All three monitors worked and the Macbook got power. I was able to drag a single window across the built-in display and the three monitors, one monitor at a time.
I didn't check anything else like resolution, refresh, etc. What's interesting, though, is that everything I've read indicates that a single USB C 3.1 or Thunderbolt port should drive only two monitors, but this does three. Weird.
DanDan
You must log in to answer this question.
protected by Community♦Jun 21 at 0:54
Thank you for your interest in this question. Because it has attracted low-quality or spam answers that had to be removed, posting an answer now requires 10 reputation on this site (the association bonus does not count).
Would you like to answer one of these unanswered questions instead?
Would you like to answer one of these unanswered questions instead?