Does the Macbook Pro M2 Max support two 4k monitors over the same USB C port?

[MntGoat]

I have a 16 inch Macbook pro M2 Max.

I currently have a USB C hub that supposedly supports 2 4k monitors. https://www.amazon.com/Anker-PowerExpand-Thunderbolt-Charging-Display/dp/B08RYZJY8M

When I connect them both through the hub, only one of them allows me to set 4K normally, the other one requires me to use scaling.

If I use HDMI on one and USB C on the other then I can do 4K on both.

If I use two USB C ports on the Macbook then I can also do 4K on both.

So is this a limitation of my hub or can I only use one 4K monitor per USB C port?

Thanks.

 

[tstafford]

The MacBook Pro has TB4 ports not USB-C (same plug type, much higher bandwidth). And yes with the proper dock you can run two 4K monitors off of one TB4 port. There are plenty that can support this. Example: Caldigit.

 

[MntGoat]

The MacBook Pro has TB4 ports not USB-C (same plug type, much higher bandwidth). And yes with the proper dock you can run two 4K monitors off of one TB4 port. There are plenty that can support this. Example: Caldigit.

The hub I have (link in the post) says it is thunderbolt 4 and claims to support 2 4k monitors. Just seems odd that it doesn't work.

 

[tstafford]

The hub I have (link in the post) says it is thunderbolt 4 and claims to support 2 4k monitors. Just seems odd that it doesn't work.

What type of cables are you using b/w the Mac and the dock and also the dock and the displays?

 

[MntGoat]

What type of cables are you using b/w the Mac and the dock and also the dock and the displays?

Between the Mac and dock I'm using the cable that came with it. Looks like a USB C cable but I guess I don't know what a thunderbolt cable might look like?

The dock to the monitors uses this https://www.amazon.com/gp/product/B07THJGZ9Z

When I've tested using two thunderbolt ports I've used those same USB c to hdmi cables.

 

[tstafford]

I'm not certain and hope that someone else weighs in, but I am concerned that a USB-C cable b/w the mac and the doc is the issue. I think you need a TB4 cable to support two 4K displays at 60Hz. Note: a TB4 cable looks a lot like a USB-C cable but may have a different marking on the connector.

 

[MntGoat]

I'm not certain and hope that someone else weighs in, but I am concerned that a USB-C cable b/w the mac and the doc is the issue. I think you need a TB4 cable to support two 4K displays at 60Hz. Note: a TB4 cable looks a lot like a USB-C cable but may have a different marking on the connector.

That's easy to test. I'll just buy a TB4 cable on Amazon and try it. Thanks.

 

[tstafford]

That's easy to test. I'll just buy a TB4 cable on Amazon and try it. Thanks.

I'm optimistic it will work. The TB4 cable carries twice the data of the USB-C (and costs like four times as much!).

 

[MntGoat]

So I came back to my office this morning and the little cable itself has the TB symbol and a 4 so I'm guessing that isn't the issue.

Also yesterday I looked at the listing and it has an image that says "doesn't support m1 macbooks" but I assume that is because those don't support multiple external monitors right? but the M2 Max does, right?

 

[tstafford]

Does appear the cable that comes with it is TB4 - so that shouldn't be the issue. Also the site says doesn't support M1 MacBooks (that would seem to refer to machines like the M1 MBA or for that matter the M2 MBA that only support one external display). An M1P or M2P should work.

My advice at this point is to reach out to Anker support. Maybe there's a firmware update or something. Or they can clarify why it doesn't work on a M2P machine that we know supports dual external displays

 

[Judy Ma]

The MacBook Pro has TB4 ports not USB-C (same plug type, much higher bandwidth). And yes with the proper dock you can run two 4K monitors off of one TB4 port. There are plenty that can support this. Example: Caldigit.

I also have same problem,your answer help me.

 

[MntGoat]

I also have same problem,your answer help me.

Are you using the same hub? I contacted Anker and they said it should be working fine so they had me send it for RMA. We'll see what happens when it comes back.

 

[xraydoc]

Also yesterday I looked at the listing and it has an image that says "doesn't support m1 macbooks" but I assume that is because those don't support multiple external monitors right? but the M2 Max does, right?

Correct. The MacBooks with the original M1 (not the M1 Pro/Max/Ultra) support only one external display. Same with the MacBook Air M2 (and 13" MacBook Pro M2).

The M1 Pro/Max/Ultra and the M2 Pro/Max (and presumably M2 Ultra if/when it comes out) support at least two external displays, so they're good to go.

 

[likegadgets]

I am running an M2 Max with a Caldigit T4 - one T4 cable to a T4 port on the MAC - driving a 6K Apple XDR and a 4K Samsung M8. Most ports on the Caldigit are running drives, USB label printer, Scanner, 1GB ethernet, 4 external SSD, a DVD writer, The monitors and all peripherals and charging work with a one cable 1 port solution. The M2 MAX replaced and M1 MAX where the same setup worked fine

 

[MntGoat]

Just got the anker replacement and it has the same issue so I don't think the device was faulty. It just doesn't seem to support dual 4k monitors with the m2 max.

 

[MntGoat]

I am running an M2 Max with a Caldigit T4 - one T4 cable to a T4 port on the MAC - driving a 6K Apple XDR and a 4K Samsung M8. Most ports on the Caldigit are running drives, USB label printer, Scanner, 1GB ethernet, 4 external SSD, a DVD writer, The monitors and all peripherals and charging work with a one cable 1 port solution. The M2 MAX replaced and M1 MAX where the same setup worked fine

Thanks for the info. Before I spend the money on the Caldigit T4, does the OS have any issues remember which windows were on which monitor when you plug the laptop back into it?

 

[likegadgets]

Thanks for the info. Before I spend the money on the Caldigit T4, does the OS have any issues remember which windows were on which monitor when you plug the laptop back into it?

I have the one with the latest firmware (the older ones can be upgraded). I have no issues so far with the cal digit. There was an issue with wired internet that required a setting, but with the latest firmware I no longer have this or any other issues. Remembers my two monitors (XDR 6K and Samsung M8 4K) just fine and all there devices works fine as well. I recently added a T4 mini hub from Satechi so I get more T4 ports (2 monitors and a T4 drive). It all works with one cable (I have the longer 2m T4 Caldigit Cable connecting the TS4 to the Mac)

 

[MntGoat]

I have the one with the latest firmware (the older ones can be upgraded). I have no issues so far with the cal digit. There was an issue with wired internet that required a setting, but with the latest firmware I no longer have this or any other issues. Remembers my two monitors (XDR 6K and Samsung M8 4K) just fine and all there devices works fine as well. I recently added a T4 mini hub from Satechi so I get more T4 ports (2 monitors and a T4 drive). It all works with one cable (I have the longer 2m T4 Caldigit Cable connecting the TS4 to the Mac)

Thanks for the extra info. The Satechi one looks interesting as well. I might consider just getting that and using the Anker connected to the Satechi for some extra ports I need.

 

[xraydoc]

does the OS have any issues remember which windows were on which monitor when you plug the laptop back into it?

There's a thread on the Mac peripherals page I think that discusses some issues with macOS not orienting displays correctly after sleep or reconnecting. I personally have zero problems with my two displays through a Caldigit TS4, but they are two Apple Studio Displays, so that may have something to do with the lack of issues. It clearly affects some people but not everyone, so I guess there's only one way to know if it will affect you or not.

Just make sure you buy your TS4 from someplace that will accept a return if it doesn't work the way you want it to with the displays you have.

 

[MntGoat]

So I got the CalDigit one. It has the latest firmware. And it has the same issue. If I use both TB4 ports with the USB C to HDMI adapters then only one gets 4K.

However the CalDigit also has 1 DisplayPort, if I use that for one monitor and the HDMI adapter for the other then both of them work.

Could the USB C to HDMI adapters be the issue? They both work individually, just not when both plugged in. They are this adapter https://www.amazon.com/gp/product/B07THJGZ9Z

 

[likegadgets]

Have you tried contacting CalDigit Support? They usually answer the phone quickly and are helpful or send them an email (they usually reply within a day). My XDR is connected a TB4 port with TB4 cables and the Samsung M8 to a TB4 port using the USB cable it came with. XDR is 6K and M8 4K both work fine at the same time. I also tried the Samsung M8 using the CalDigit branded Display port to HDMI adapter and it also worked at 4K at the same time as the XDR. I prefer the USB connection for the M8 in case I want to use the sound or cameras of the M8 (which frankly, I do not use).

 

[MntGoat]

I haven't yet, just got the CalDigit TS4 a few minutes ago, all I did was make sure the firmware was up to date and tested it to see if it worked.