MacBook Pro M4 with thunderbolt 5 and portable monitor

Hmm. Well since you mentioned you connected the portable display using the a video/data USB-C cable on the dock's labeled USB-C DP alt port, did you use the built-in USB-C cable on the dock has to go to your Mini?

Maybe try another cable if possible? The dock has DP Alt so that should work without fail I feel like so long it's connected properly.

If this doesn't work, sorry it didn't. I've tried other portable monitors and cables, and it's worked every time. At least Amazon has a generous return policy!

Out of curiously and to test my theory, have you upgraded to 15.0?

I posted a comment just now, but don't know how to link it as I just signed up to post on here the first time because this is frustrating me so much. The gist of it was "I got the m4 Pro upgraded to Sequoia, monitor wouldn't work. After a few days decided to got back to my M1 for the time being, had to update as my last Time Machine was on Sequoia and now even it won't detect the monitor when it was perfect right before hand"

BigSnuffy wrote:

Sorry for the confusion Grant, I seemed to have hijacked dragos's original post with my own different one.

I was just wondering why my M4 Pro Mac mini can't do what my M2 Pro Mac mini does, i.e. power the same 15 inch portable monitor on its own without requiring external power, I'm using the same cable on both. Could it be something to do with the Thunderbolt 5 port.

Here's my understanding of the specifications. I could be wrong.

USB 2.0 – A host port should provide up to 2.5W of 5V power (500mA @ 5V).

USB 3.0 – A host port should provide up to 4.5W of 5V power (900mA @ 5V).

USB-C – Cables should be capable of carrying 15W of power (3A @ 5V), however this requirement in and of itself does not obligate a USB-C host port to provide 15W of power. (If I look at the fine print on the bottom of my 29W Apple USB-C power brick, it says "Output: 14.5V == 2.0A (USB PD) or 5.2V == 2.4A" – that is to say it offers only 12.48W of non-negotiated 5V power, which would be within a generic USB-C cable's safety margin.). If you were to plug a USB accessory that only speaks USB 3.* (not Power Delivery) into a USB-C port, that accessory should not expect to be able to draw more than 4.5W from that port.

USB-C – Power Delivery allows provision of up to 240W of power (5A @ 48V) in either direction – if both devices agree, and the cable has embedded chips to indicate that it is safe to use it for USB-C Power Delivery. (The first version of Power Delivery only supported delivery of up to 100W (5A @ 20V), which is why the 16" M1 {Pro / Max} MBPs can fast-charge over MagSafe 3 but not over USB-C.)

NOTE: If you connect two devices that support USB-C Power Delivery with a USB-C cable that does not, the negotiation of high levels of power delivery should, and likely will, fail. This is a safety precaution to keep you from, say, running 100W of charging power into a laptop over a cable that can only safely handle 15W.

Thunderbolt – On devices that support Thunderbolt 3 and USB4, one Thunderbolt port should provide a minimum of 15W (3A @ 5V) of power; others can provide as little as 7.5W (1.5A @ 5V) of power. I believe that Thunderbolt 4 (and 5) may raise that minimum requirement to 15W (3A @ 5V) on all Thunderbolt ports. A host with Thunderbolt ports may offer more power / higher voltages to accessories (via PD negotiation), but is not required to do so.

I'm not sure if the 15W or 7.5W minimum applies if a port is operating in a NON-Thunderbolt mode, such as USB 3.* mode or DisplayPort Alt Mode.

<<. So I think we all should make some noise so Apple resolves this problem asap. >>

Apple expends engineering money to fix well documented issues that come to it in a complete package through the formal Bug Report process. There should be enough information included in a formal Bug Report package that Apple can replicate the same issue in their laboratories.

Gratuitous 'noise making' in simply not productive. When you make noise HERE, all it does is disturb other Users like you. Apple does not read these forums searching for inspiration -- they are too busy researching formal Bug Reports.

yskandar thaddé wrote:

Because I recently bought my display (one with old firmware) they send me a replacement one which was flashed for the new Mac USB c ports( took a coole of weeks to arrive) And the new display works fine now. This shows that the problem is a software one. That a company as espresso display managed to solve the problem in a couple of weeks after the new MacBook pro’s came on the market and with the right firmware it works perfectly. I think that Apple should react as quick and decisive to solve this problem for their users.

If it took a software update to the external monitor to change the behavior – wouldn't that suggest an issue with the code in the external monitor?

If the other monitors likewise are in need of software fixes, wouldn't that be their manufacturers' responsibility?

If ports are suppose to be reversed compatible and the implementation of it on a MacBook is not why is it anther manufacturers problem to solve it ? Why is not apples responsibility with all there huge team of tech guys and spending a lot of money to solve issues and up till now they only came up with it is “ your problem not mine go buy a new monitor “ At least the vendor (espresso display) try to solve a

pronlem that they did not create as we see in this posts a lot of other vendors tell their customers good luck same as Apple

Fine but the original q was if others are having the same problem and is Is it display , Mac, hardware or sf issue. To quote you new ports should be reversed compatible. A small vendor managed to solve the problem because one user of there display contacted them they identified the problem and solved it wit a firmware update on their side. As you suggest Apple spends huge amounts of money and a big big engendering team to solve problems. Why is it still not solved as many of you guys have contacted Apple support a lot of times ? Apple changed something new port as it took a simple firmware update to make the portable display to work again why can’t apple update their port firmware so their users can go back to their work without having to use a lot of work arounds.

maybe with your knowledge and time spent here can formulate a nice bug report to help your engendering friends who are to busy reading bug reports. And don’t agree with you that Apple does not read or scan these forums. I think they do. Maybe as a representative or as a user community member.

Same experience with the UPERFECT 4K, it’s a good work around and also shows that the Mac is supplying the power the monitor is requesting through the Thunderbolt port. Blows me away that my m3 MacBook Air can provide power and signal over one cable with no issue but my “Pro” grade M4 $3500 juggernaut cannot.

I asked Plugable Technologies to test its USB-C portable monitor for laptop (USBC-PDMON) which has 2x 10Gbps USB-C ports for data or connecting peripherals, 100W PD pass-through (85W charging), 15.6” IPS display, cover/stand with a M4 Pro 14" MacBook Pro using one of the T5 ports. Looks like it works:

We've tested the USBC-PDMON with a MacBook Pro (14-inch, 2024, M4 Pro) and they worked well together. The portable monitor was able to successfully show video from the Mac, and the other functions such as the 10Gbps USB hub ports and Power Delivery pass-through also worked well.

Just passing that information on to those who are interested. Obviously contact the company to make certain before you buy it.

David S. wrote:

I asked Plugable Technologies to test its USB-C portable monitor for laptop (USBC-PDMON) which has 2x 10Gbps USB-C ports for data or connecting peripherals, 100W PD pass-through (85W charging), 15.6” IPS display, cover/stand with a M4 Pro 14" MacBook Pro using one of the T5 ports. Looks like it works:

We've tested the USBC-PDMON with a MacBook Pro (14-inch, 2024, M4 Pro) and they worked well together. The portable monitor was able to successfully show video from the Mac, and the other functions such as the 10Gbps USB hub ports and Power Delivery pass-through also worked well.

Just passing that information on to those who are interested. Obviously contact the company to make certain before you buy it.

Exactly WHERE were they connecting the power supply? All these displays work if you connect a power adapter to the DISPLAY. The issue is whether they can negotiate to get enough power from the Mac across ONE interface from the MAC's ThunderBolt-5 port.

I sent a followup to Plugable asking them whether the portable monitor supports power and video through one USB-C cable, or whether a second USB-C cable must be used to independently provide power to the display.

Yes, some work, some don't.

Tried two. An Innoview 18" (very nice, btw) potable does NOT work with Mini M4 Pro, yet works with M3 Macs, and probably M4 Macs without TB5. However, A UPerfect 16" DOES work with TB5, so there's that, go-figure

Fix for Innoview is to use HDMI and then a USB-C cable from the front of the Mini to power it. Hopefully, this is a temporary fix, as there's something amiss with TB5 presently.

So everyone, don't even bother except to let Apple know, so they can hopefully patch this. It's pretty clear cut at this point. I'm using Apple's TB4 cables, which are enough, so....

note: Also tried a TB5 cable I had, doesn't work either, which was expected.

I did actually test with various cables and monitors and even compared to their MacBook Pro M4 with the regular, pro, and max chips. They and Apple, who was on the phone with me, advised it’s only the M4 Pro/Max MacBook Pros that have the TB5 ports and that the port PD protocol isn’t allowing power and av to be transmitted. So, I can actually get one monitor to work with external power, but that’s it. I was also unable to get any of the six unpowered hubs to work. This is just silly.

And I too believe it can be fixed with an older OS (not doing that though) or a software update, but they literally said it was the TB5 port configuration and set up to deliver less power to preserve the MacBook power.

tbh it's increbily easy to follow up on long threads, and it's been done like this literally since Internet was just a "local network" between universities. It's just how this specific Apple forum work, by ordering the messages apparently at random, based on "rank". So whenever it goes past one page, it's a mess, and users keep replying to months old, outdated messages like they've been written yesterday.

Setting the replies ordering by "oldest" returns back to the usual organization that worked for the whole world since last century, and most messages will make sense

This is very highly dissapointing from Apple. As someone who has spent about 75-100k on apple devices over 10 years it's astounding to me that a company can make such great devices and forget to check anything for compatibility. Certainly they thought hey let's check portable monitors.

Anyways I have an Apildella tri monitor with 2 15 inch monitors or maybe 14. Worked great with my M1 macbook pro. Wont work with the Macbook Pro M4. Kind of comical since my M1 screen stopped workign so I guess if I thr0w them all together in a blender it should be perfect.

Anyways are there any dual (so you have 3 monitor) 14 inch or 15 inch screens that work with one cable to M4 Macbook Pros? Seems easier to buy one than figure this out. TY