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Is there a way to get a 2020 MacBook Air (M1) to drive two external displays, specifically where one of the displays does not have USB-C/Thunderbolt?

The Macbook Air has two USB-C ports (both "Thunderbolt/USB4" according to the spec on apple.com). But while one of the displays (an LG Ultrafine 5K) also has USB-C ports (four of them in fact); the other (a Samsung U32H85x) has no USB-C at all; instead it has a mixture of other options, including HDMI, DisplayPort, and miniDisplayPort.

So far I have been using a port "expander" widget to convert one of the Macbook Air's USB-C ports to HDMI to drive the Samsung. Doing that, I have been able to drive either of the displays from the laptop, but not both at the same time. So I can have:

From and via To
EITHER
USB-C on MacBook Air [USB-C_to_USB-C Cable] USB-C on LG Display
OR
USB-C on MacBook Air [USB-C_to_HDMI_Adapter] [HDMI_to_HDMI Cable] HDMI on Samsung Display
BUT NOT BOTH

However, I am able to drive both displays at the same time if I use an older laptop -- a 2019 MacBook Pro (with Intel Silicon). That is, I can have:

From and via To
USB-C on MacBook Pro [USB-C_to_USB-C Cable] USB-C on LG Display
AND
USB-C on MacBook Pro [USB-C_to_HDMI_Adapter] [HDMI_to_HDMI Cable] HDMI on Samsung Display

Even there, whether I can drive both displays at the same time depends on which particular two of the 2019 Macbook Pro's USB-C ports (it has four in total) I choose. (And obviously I still need to convert one to HDMI using the expander widget so I can drive the Samsung.)

But, back to my current laptop; is it even possible for the newer 2-port Air with M1) to drive two displays at all? If so, is it possible to do it where only one of the displays is driven by USB-C/Thunderbolt

thanks.

3 Answers 3

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The interfaces on the monitors are irrelevant, other than the need of appropriate cables.

The M1 Air, however, can only drive one external monitor. If you want to use two, you need a dock that implements DisplayLink.

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But, back to my current laptop; is it even possible for the newer 2-port Air with M1) to drive two displays at all?

Unfortunately, no...

To give you a quick answer to your your question, the 2020 MacBook Air M1 only drives a single external monitor. This is documented on both Everymac.com and on Apple's Official Technical Specifications page.

Ports don't drive an external display monitor...

If so, is it possible to do it where only one of the displays is driven by USB-C/Thunderbolt

I wanted to address this here, because it appears to be some misunderstanding on how displays are driven.

The ports on your MacBook are Thunderbolt 3/DisplayPort. The Thunderbolt signal includes USB. The connector is Type-C and doesn't impact how many monitors you can connect to your Mac.

It's the GPU and DisplayPort bandwidth that dictates how many displays you can connect. As such, this particular Mac can only drive a single external monitor.

So far I have been using a port "expander" widget to convert one of the Macbook Air's USB-C ports to HDMI to drive the Samsung. Doing that, I have been able to drive either of the displays from the laptop, but not both at the same time.

That's not an "expander;" It's a DisplayPort to HDMI converter. In the past, if you wanted to add another monitor to a MacBook that wasn't capable of driving an additional display, you'd add a USB to Video adapter. This is like adding another video card in a PC. I currently (personally) haven't tested any with the Silicon MacBooks

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    Thanks. I'm starting to conclude that the best solution to my problem is to just get a new Mac; something with an M2 Pro or M2 Max. I should probably start to rehearse my speech to my wife: "But honey, the guys on StackExchange said I have to get a new Mac..."
    – tkp
    Jun 29, 2023 at 0:19
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    That question right there and it's potential answers would undoubtedly be the highest voted by var.
    – Allan
    Jun 29, 2023 at 1:42
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Apple designed your MacBook Air to be limited to one external display. Below describes a possible way overcome this limitation by adding a second external display.

You need to replace the “USB-C to HDMI Adapter”, used with the Samsung display, with an adaptor or dock which uses DisplayLink or similar technology. The maximum resolution of the Samsung display is 3840X2160@60Hz. One such adaptor, which would be capable of this maximum resolution, is the OWC USB-C to Dual HDMI 4K Display Adapter with DISPLAYLINK. This adaptor contains the DL-6950 chipset. According to the 6950 chipset documentation, you should be able to plug this adaptor into a USB-C port on the Mac or the LG display. According to OWC, this adaptor is compatible with your MacBook Air.

To use DisplayLink, your Mac will need to install software. I could not find any documentation which throughly explains how DisplayLink works. However the User Guide for the OWC adaptor explains Screen Recording will need to be allowed, as shown in the image below.

screen recording

From this, I surmise the following is taking place.

  • Software is used to create internal display.
  • The video on this internal display is recorded.
  • The video is compressed and sent by USB to the adaptor.
  • DL-6950 chip converts the compressed video to HDMI.
  • The HDMI is sent to the display.

Be aware, some of the above is conducted by the Mac's M1 chip and thus may cause a slowdown in the Mac's performance.


Note: I could find other cheaper adaptors with only one HDMI output. However, these adaptors are not capable of 3840X2160@60Hz. The best I could find reached a maximum of 3840X2160@30Hz.

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  • Thanks. I've ordered the OWC adapter you described, so let's see how that goes. In fact the "USB-C to HDMI Adapter” I said I used -- what I referred to as a "port expander" but which @Allan corrected -- is a SATECHI USB-C Multiort Hub. But I guess that while it is a level up in functionality compared with Apple's A2119 (which I'd also tried), it is still not providing whatever extra the 6950 silicon is making available in the OWC. Sigh -- I'm not a civilian in this stuff, and I'm still clueless. How your average grandma Jan or great uncle George is meant to figure it out, who knows.
    – tkp
    Jun 28, 2023 at 23:46

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