Cannot Connect More Than 2 External Monitors to MacBook Pro M3

The same rules we learned for the M1 and M2 still apply. Display interfaces are generated deep inside the system on a chip. How many there are depends on the exact type of Processor:

M3 (plain) like the 13-in and 15-in supports up to ONE fully hardware-accelerated external display.

M3 PRO processor supports up to Two fully hardware-accelerated external displays.

M3 MAX processor supports up to Four fully hardware-accelerated external displays.

In every case, turning off the internal display does Not allow you to connect another external display.

Tech Specs now available here:

MacBook Pro - Tech Specs - Apple

Hi, Stephane074, this link says your MacBook will do 2 external monitors;

https://plugable.com/en-ca/blogs/news/the-new-apple-m3-macbook-pro-have-arrived-and-here-are-the-compatible-products-that-we-have-tested

john B

DisplayLink technology creates a "fake" display buffer in RAM, sends the data out over a slower interface to a stunt box with DisplayLink custom chips that put that data back onto a "legacy" interface. It is not a true "accelerated" display, and it can suffer from lagging. Just adding the DisplayLink Driver is not adequate to get a picture -- you need a DisplayLink "stunt-box" or a Dock that includes DisplayLink chips.

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It may be acceptable for a second display showing slow-to-change data such as computer program listings, stock quotes, or spreadsheets, but NOT for full motion Video, not for Video editing, and absolutely not for gaming. Mouse-tracking on that display can lag, and can make you feel queasy.

In a pinch, it may even play Internet videos (as one user put it) “without too many dropped frames".

If you are only doing program listings spreadsheets, stock quotes, and other slow to change data, DisplayLink can work for you, but requires you to make some strong compromises.

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It is really nice to know that you can use a DisplayLink display if you MUST have an additional display for some of the types of data I mentioned. But that is NOT the same as the computer supporting a second, built-in, Hardware-accelerated display.

These displays depend on DisplayLink software, and are at the whim of Apple when they make MacOS changes. There have been cases where MacOS changes completely disabled DisplayLink software, and it took some time for them to recover.

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I think the Big Surprise for a lot of Hub/Dock buyers is that they thought they were getting a "real" display, but actually got a DisplayLink "fake" Display. If you got what you expected in every case, I would not use such pejorative terms to describe DisplayLink.

in order to support up to TWO displays on one cable out of the Mac, the Port, the Cable and the first device (Dock or Display) must all be genuine Thunderbolt.

USB-C has fewer conductors, and does not support the same amount of data.

Grant Bennet-Alder wrote:

The same rules we learned for the M1 and M2 still apply. Display interfaces are generated deep inside the system on a chip. How many there are depends on the exact type of Processor:

M3 (plain) like the 13-in and 15-in supports up to ONE fully hardware-accelerated external display.

M3 PRO processor supports up to Two fully hardware-accelerated external displays.

M3 MAX processor supports up to Four fully hardware-accelerated external displays.

f you throw in the desktops, you can generalize the rules. I.e., M2 supports up to two displays total – including any built-in one. (Which jibes with the M2 Mac mini supporting two external displays – while 13" and 15" M2 MacBook Airs and 13" M2 MacBook Pros support only one.)

In every case, turning off the internal display does Not allow you to connect another external display.

That's true of current Apple Silicon MacBook Pros – and of most Apple Silicon notebooks and iMacs, period.

The 13" and 15" MacBook Airs are an exception. They can drive a second external display (with lower maximum resolution) when, and only when, their lids are closed. (The lower 5K resolution limit may translate into not being able to use any Retina mode higher than "like 2560x1440" with a 4K monitor.)

News reports say that Apple plans to bring that feature to the 14" M3 MacBook Pro via a software patch. There isn't any announced date for the release of this patch, and for now, the limit for the 14" M3 MacBook Pro is ONE external display.