MacBook Pro M4 with thunderbolt 5 and portable monitor

Now that we know it's a TB5 port compatibility issue, does anyone know which portable monitors (other than the one linked by calirap, which is only 16 inches and also unavailable now) actually work unplugged from auxiliary power with TB5? How can we be sure when we're shopping for a new monitor? Any recommendations would be appreciated. If you find one on line, 18" or bigger, please post. Thank you.

Hello, I had the same issue and the same answer from Apple Support by phone and technicall service directly on the store, nobody who works there knows anything.

I have a M4 pro Max and couldn´t make my portable monitor work (it is thuntherbolt 3 and 4) with only one cable from my macbook, (like i used to do it with my intel and M1 macbook). I tried buying different cables and hubs, but the only thing that worked was to connect the monitor direclty to the AC and then the powered monitor with only one cable to my Macbook. Thats the definitive solution.

I even make it work with 3 external monitors, 2 monitor connected directly to the AC and then each monitor with one cable to my macbok. the 3th monitor worked with a HDMI cable.

As far as I undestand, apple is trying to protect the battery of the macbook by not transmiting power though their port tunberbolt5 port, only receiving. My macbook is even charging from the monitor USB contection.

Hope this can be usefull for all who is having this problem.

Just received this response back from Arzopa about their portable monitor.

We are sorry that our monitor models are not currently compatible with Thunderbolt 5 ports. You can connect via HDMI+power cable or connect the monitor to other devices.

Arzopa Customer Service Team

If you are looking for a separate monitor that does work, please start a new topic thread.

As a frequent contributer to this community, I have observed:

• This thread is primarily about those monitors that are affected by this bug.
• That would logically mean finding one that works in this thread would actually have less odds of success than outside the thread.

And based on your response saying you want one that is sold in Amazon UK, what would really help is the Make and model number of the said monitor. That way you could search Amazon, as well as other resellers in the UK.

I just tried and this works.. funny.

Technically this also can be addressed using some external power back, but you right, main idea is to avoid using any extra connection to have second monitor working

lindowmac wrote:

I will say though USB4 =/= Thunderbolt 4.

Yes. This. My understanding is that

• USB4 host ports can optionally support USB4 40 Gbps transfers.
• USB4 host ports can optionally support Thunderbolt Alt Mode. While the USB4 specification is based upon Thunderbolt 3, it is also possible to implement Thunderbolt 4 or Thunderbolt 5.
• Thunderbolt 3 support does not automatically imply USB4 support. There are many Intel Macs that support Thunderbolt 3, but that predate USB4.
• Thunderbolt 4 came after Thunderbolt 3 and USB4, and Intel has attempted to use the Thunderbolt 4 specs and certification requirements to force cleanups, in the way of making once-optional features mandatory on equipment that is Thunderbolt-4-certified.

Yes, it is a different machine. But:

• If what you are saying is true....why did that same portable monitor work with the non powered USB C display hub I used as the in-between? If the issue was power as you claim, why would the NON-powered hub placed between the thunderbolt 5 port and the portable monitor make it work suddenly?
• The reality of our situation is that, regardless of how things 'should work', portable monitors that have worked on my M1 Max MBP, my brothers M2 Pro MBP, my friend's M2 Pro Mac mini, my plain M4 Mac mini....those same monitors are not working on the M4 Pro Mac mini. Nor is the portable monitor working on OP's Mac. Regardless of what is being said, there is a change in results based on the introduction of the M4 Pro featuring thunderbolt 5 ports.
• Why are you trying using numbers to support the idea that it shouldn't work on the M4 Pro Mac Mini but then speculative logic to support why it did work on the plain M4 and calling it 'lucky'? This isn't super helpful. I am trying to provide useful information based on real world results. Saying something "should" or "shouldn't" work while staring at results in the face doesn't really bring anything to the table here, nor does calling something "lucky".
• Where did you get the numbers saying the Mac mini wasn't designed to deliver a certain amount of power? I am not calling you wrong, I just don't know where you got that from. I don't see it listed in the device specs and as you pointed out, the OP's machine and the Mac mini are different machines so we can't really rely on the numbers provided in this thread.

This works if your monitor has two USB ports:

1. plug portable monitor into a charger so it can get power.
2. Then plug it using a second cable into the M4 (thunderbolt) so it can get signal.

Mine kept saying "no signal" when I guess it really meant "help no power!"

I have the same issue, I actually work in the portable monitor business, this is a massive issue for us. 80% of our monitors and competitors monitors don't work with M4 Macs (they work with M1 Macs).

I’ve got a similar problem, but with a M2 pro Mac mini vs a M4 pro Mac mini

Same monitors, same cables. (Thunderbolt 4 cables) Works fine with the M2 pro, Mac mini powers both monitors, but M4 pro Mac mini won’t even power one of them. 

Same problem. I had a Macbook Pro M2 Pro, used with my portable display, worked flawlessly. Got this Macbook Pro M4 Pro now, and with same display cable and same portably display, it doesn't work. Portable display states "No Signal".

Rather that fruitlessly post what cable and portable display I am using, likely shouldn't matter: it worked with my M2 Pro MBP, so I feel via backwards combatibility should work with this new M4 Pro MBP.

lindowmac wrote:

Rather that fruitlessly post what cable and portable display I am using, likely shouldn't matter: it worked with my M2 Pro MBP, so I feel via backwards combatibility should work with this new M4 Pro MBP.

Maybe the problem is that the portable monitor is being overly demanding of bus power – and that while the M2 Pro MBP was generous with handing out extra bus power, that doesn't necessarily mean that anything is wrong with the M4 Pro MBP.

Since you haven't been able to get any reports from the computer about how much power the external monitor wants to suck out of the MBP, and since you haven't told us which external monitor it is (which might lead us to specifications or manuals for that monitor, on the Web), we don't know what it's trying to do.

All we know is that you seem to want the MBP to power an external display about which there are no specifics. That's not much of a basis for troubleshooting.

My feeling is that you should assume that an external display needs its own power source (whether that is wall power, or a battery of its own) until proven that its demands are within what a notebook is willing to supply.