M1 Pro MBP - Trying to connect 2 monitors via USB C hub

[izzy0242mr]

I have a Gvrioy USB Hub device which can receive power via USB C Power Delivery, has 2 HDMI ports, a DisplayPort, and some USB ports.

I have an M1 Pro MBP (so capable of driving 2 external displays + the built-in laptop display).

I want to use this USB hub (or any USB C hub) to connect to one USB C port on my Mac to receive power and drive both external displays, which are connected to the hub via HDMI and DisplayPort.

Here's what happens:

Scenario 1: Monitor A is connected to hub via HDMI. Monitor B connected to hub via DisplayPort. Hub connected to Mac via USB C. Monitor A isn't detected as a third display, but both displays work (mirroring each other). So, Monitor B is detected in System Preferences, but everything shown on Monitor B is also shown on Monitor A.

Scenario 2: Monitor A connected to hub via DisplayPort, Monitor B connected to hub via HDMI, hub connected to Mac via USB C. Neither monitor is detected at all.

Scenario 3: Monitor A connected directly via HDMI to Mac. Monitor B connected to hub via DisplayPort, and hub then connected to Mac via USB C. Both monitors detected and independently adjustable.

Scenario 2 works without issue on my Windows PC. I'd like it to work on my Mac, too, so I don't have to unplug one device when switching between Mac and PC. Any suggestions? Open to buying a different hub if it would work, just am not sure what the root of the issue is (beyond "Apple Silicon").

 

[Bigwaff]

MBP can support two external displays over Thunderbolt. You will need a TB hub with HDMI/DisplayPort/USB. MBP can support a display via HDMI and via TB/USB for two external displays. If you want two external displays via single USB, you need a USB hub which supports DisplayLink.

How many displays can be connected to MacBook Pro - Apple Support

The number of external displays that you can use at the same time depends on your Mac model and the resolution and refresh rate of each display.

support.apple.com

 

[CalMin]

I don't know the technical reasons for any of it but I also had various challenges in getting my monitors to work with my 14" M1 Pro. Then I bought a CalDigit dock and it all worked as it was supposed to. I tried all sorts of other dongles and docks and there were always issues/glitches.

It's also pick about which cables are used so there's that too... Good luck!

 

[izzy0242mr]

MBP can support two external displays over Thunderbolt. You will need a TB hub with HDMI/DisplayPort/USB. MBP can support a display via HDMI and via TB/USB for two external displays. If you want two external displays via single USB, you need a USB hub which supports DisplayLink.

How many displays can be connected to MacBook Pro - Apple Support

The number of external displays that you can use at the same time depends on your Mac model and the resolution and refresh rate of each display.

support.apple.com

Got it, thanks. So sounds like I need to get a proper Thunderbolt-capable hub.

I don't know the technical reasons for any of it but I also had various challenges in getting my monitors to work with my 14" M1 Pro. Then I bought a CalDigit dock and it all worked as it was supposed to. I tried all sorts of other dongles and docks and there were always issues/glitches.

It's also pick about which cables are used so there's that too... Good luck!

Thanks both! I'm unfortunately looking for something way cheaper than a CalDigit dock—but thanks for helping document what has worked. I'm hoping to stumble across a used Thunderbolt 3 dock that has both HDMI and DisplayPort ports, but I'm wanting something under $50, and ideally closer to $30-35. I've seen the Belkin Thunderbolt 3 Dock Core, but I've seen mixed reviews both on Amazon and I think here on MacRumors. That's the most I'd want to spend on such a dock though.

 

[CalMin]

Got it, thanks. So sounds like I need to get a proper Thunderbolt-capable hub.

Thanks both! I'm unfortunately looking for something way cheaper than a CalDigit dock—but thanks for helping document what has worked. I'm hoping to stumble across a used Thunderbolt 3 dock that has both HDMI and DisplayPort ports, but I'm wanting something under $50, and ideally closer to $30-35. I've seen the Belkin Thunderbolt 3 Dock Core, but I've seen mixed reviews both on Amazon and I think here on MacRumors. That's the most I'd want to spend on such a dock though.

I understand. And yes, I was in the same mindset when it came for paying for a Caldigit and only ponied up the funds when nothing else worked reliably. I didn't have high hopes but in the end I glad I spent the money because it's worked solidly ever since.

Best of luck finding something less expensive. These first gen. Apple silicon Macs were finicky with their display compatibility. (then again my 2019 Intel MBP, was also a pain!)

 

[izzy0242mr]

I understand. And yes, I was in the same mindset when it came for paying for a Caldigit and only ponied up the funds when nothing else worked reliably. I didn't have high hopes but in the end I glad I spent the money because it's worked solidly ever since.

Best of luck finding something less expensive. These first gen. Apple silicon Macs were finicky with their display compatibility. (then again my 2019 Intel MBP, was also a pain!)

I have a Belkin Thunderbolt 3 Express Dock HD which I got for cheap, but it doesn't work with my PC or my Mac for some reason even though it seems to be in good condition. Giving me similar errors and not really sure why. Could well be the M1 thing.

 

[teh_hunterer]

MBP can support two external displays over Thunderbolt. You will need a TB hub with HDMI/DisplayPort/USB. MBP can support a display via HDMI and via TB/USB for two external displays. If you want two external displays via single USB, you need a USB hub which supports DisplayLink.

How many displays can be connected to MacBook Pro - Apple Support

The number of external displays that you can use at the same time depends on your Mac model and the resolution and refresh rate of each display.

support.apple.com

You can do two displays via a single Thunderbolt cable. One display can come from the dock's DisplayPort, and the other display can come from a USB-C to DisplayPort/HDMI cable from the dock's downstream Thunderbolt port.

That does mean you need a Thunderbolt dock that has a downstream Thunderbolt port, but plenty do.

 

[teh_hunterer]

I have a Belkin Thunderbolt 3 Express Dock HD which I got for cheap, but it doesn't work with my PC or my Mac for some reason even though it seems to be in good condition. Giving me similar errors and not really sure why. Could well be the M1 thing.

Have you tried this:

Plug one monitor into the DP port, and the other into the secondary TB port (USB-C to DP or USB-C to HDMI).

Unless the dock itself doesn't work at all?

Dual external displays is unfortunately really fiddly on the Mac. Windows will do dual displays over USB-C or Thunderbolt, using 'MST' (multi-stream transport), so it's not fussy at all. Mac won't do dual displays over USB-C at all because it doesn't support MST. It will do it over Thunderbolt, but only if one of the displays is connected via the dock's secondary Thunderbolt port.

Annoying, expensive, but it does work. And it'll continue working on Windows if you wire it up that way.

 

[izzy0242mr]

Have you tried this:

Plug one monitor into the DP port, and the other into the secondary TB port (USB-C to DP or USB-C to HDMI).

I had tried USB C port (display) to USB C port (dock), using an Apple Thunderbolt cable. But that may be the problem. I haven't tried a DP to USB C or HDMI to USB C on that same monitor.

Can the HDMI or DP-to-USB C be any USB C or does it need to be HDMI or DP to Thunderbolt?

 

[teh_hunterer]

I had tried USB C port (display) to USB C port (dock), using an Apple Thunderbolt cable. But that may be the problem. I haven't tried a DP to USB C or HDMI to USB C on that same monitor.

Can the HDMI or DP-to-USB C be any USB C or does it need to be HDMI or DP to Thunderbolt?

I'm a little confused by your terminology here.

If you can, I would do this:

Dock's DisplayPort port > DP cable into 1st monitor's DP port.
Dock's second Thunderbolt port > USB-C to DP cable into 2nd monitor's DP port

 

[BeatCrazy]

I had tried USB C port (display) to USB C port (dock), using an Apple Thunderbolt cable. But that may be the problem. I haven't tried a DP to USB C or HDMI to USB C on that same monitor.

Can the HDMI or DP-to-USB C be any USB C or does it need to be HDMI or DP to Thunderbolt?

You’re never going to get dual independent external monitors with one Thunderbolt connection into a USB-C dock. You need a Thunderbolt dock.

If you get a Thunderbolt dock, you can use USB-C to HDMI/DP. Doesn’t need to be a Thunderbolt-specific adapter.

 

[teh_hunterer]

You’re never going to get dual independent external monitors with one Thunderbolt connection into a USB-C dock. You need a Thunderbolt dock.

If you get a Thunderbolt dock, you can use USB-C to HDMI/DP. Doesn’t need to be a Thunderbolt-specific adapter.

He apparently also has a "Belkin Thunderbolt 3 Express Dock HD". Will be interesting to see what happens if he tries plugging in as I mentioned above.

 

[izzy0242mr]

He apparently also has a "Belkin Thunderbolt 3 Express Dock HD". Will be interesting to see what happens if he tries plugging in as I mentioned above.

Yep. I just ordered an HDMI to USB C cable and plan to try it and report back. I'm still skeptical it'll work, though, because the Windows PC gave me errors saying it couldn't detect the dock when I connected it even with just one monitor connected. That's probably a Windows problem, but I will update after I get the cable.

 

[teh_hunterer]

Yep. I just ordered an HDMI to USB C cable and plan to try it and report back. I'm still skeptical it'll work, though, because the Windows PC gave me errors saying it couldn't detect the dock when I connected it even with just one monitor connected. That's probably a Windows problem, but I will update after I get the cable.

Just to avoid confusing people, generally that's called a USB-C to HDMI. USB-C on the dock, HDMI on the monitor. If you say it back to front you'll confuse people.

 

[izzy0242mr]

Just to avoid confusing people, generally that's called a USB-C to HDMI. USB-C on the dock, HDMI on the monitor. If you say it back to front you'll confuse people.

I learn something new all the time. Thank you! Had no idea the order mattered for that!

 

[izzy0242mr]

Have you tried this:

Plug one monitor into the DP port, and the other into the secondary TB port (USB-C to DP or USB-C to HDMI).

Unless the dock itself doesn't work at all?

Dual external displays is unfortunately really fiddly on the Mac. Windows will do dual displays over USB-C or Thunderbolt, using 'MST' (multi-stream transport), so it's not fussy at all. Mac won't do dual displays over USB-C at all because it doesn't support MST. It will do it over Thunderbolt, but only if one of the displays is connected via the dock's secondary Thunderbolt port.

Annoying, expensive, but it does work. And it'll continue working on Windows if you wire it up that way.

Dude, you're a genius. This worked. Weirdly, I had to end up switching cables between the machines—Monitor A connected to Belkin dock via DP and Monitor B connected to Belkin dock via USB C to HDMI cable wasn't working. Worked on Windows, and macOS detected all 3 monitors, but Monitor B was flickering and wouldn't show an image. So I switched the cables for each monitor and now they all 3 work across both Mac and Windows! I'm saved! Huge thanks.

Edit: so...the displays are working as I said, but I just realized that my Windows laptop isn't getting power from the dock - or not enough power because it almost died on me despite being plugged in. Haven't tested that with the Mac yet.

Edit 2: Seems like some Redditors have found that this dock doesn't charge Windows PCs correctly due to some lack of drivers. Not ideal, but I'm still happy the dock now works with both devices even if it only charges one of them.

 

[teh_hunterer]

Dude, you're a genius. This worked. Weirdly, I had to end up switching cables between the machines—Monitor A connected to Belkin dock via DP and Monitor B connected to Belkin dock via USB C to HDMI cable wasn't working. Worked on Windows, and macOS detected all 3 monitors, but Monitor B was flickering and wouldn't show an image. So I switched the cables for each monitor and now they all 3 work across both Mac and Windows! I'm saved! Huge thanks.

Edit: so...the displays are working as I said, but I just realized that my Windows laptop isn't getting power from the dock - or not enough power because it almost died on me despite being plugged in. Haven't tested that with the Mac yet.

Edit 2: Seems like some Redditors have found that this dock doesn't charge Windows PCs correctly due to some lack of drivers. Not ideal, but I'm still happy the dock now works with both devices even if it only charges one of them.

Hey, glad to help! It's a shame it has to be so complicated on the Mac side.

That dock apparently supplies 85w which is well more than enough for any MacBook with an M1/2/3 Pro. Some Windows laptops (gaming mostly) consume more power than that, and some annoyingly refuse to even charge at all over USB-C.

What Windows laptop are you using?

 

[izzy0242mr]

Hey, glad to help! It's a shame it has to be so complicated on the Mac side.

That dock apparently supplies 85w which is well more than enough for any MacBook with an M1/2/3 Pro. Some Windows laptops (gaming mostly) consume more power than that, and some annoyingly refuse to even charge at all over USB-C.

What Windows laptop are you using?

I have a Lenovo Thinkpad that usually uses a 65 watt charger. It's a basic work laptop, nothing fancy. Pretty sure it's some "feature" where the manufacturer artificially limits hardware that they don't make.

Oh well.

 

[teh_hunterer]

I have a Lenovo Thinkpad that usually uses a 65 watt charger. It's a basic work laptop, nothing fancy. Pretty sure it's some "feature" where the manufacturer artificially limits hardware that they don't make.

Oh well.

What's the exact model of the Thinkpad? It may not charge over its USB-C port, but it could be as simple as you having to allow that Thunderbolt dock in the settings.

Edit: Ah right you found something about the dock not charging Windows stuff correctly. Missed that.