How many External monitors will connect via Dock on M1 macbook?

Your subject line says that you have a "M1 MacBook" and your tag line further identifies it as a 13" MacBook Pro – with a plain M1 chip. That notebook supports "one external display with up to 6K resolution at 60 Hz."

MacBook Pro (13-inch, M1, 2020) - Technical Specifications - Apple Support

There are no hubs, docks, or adapters that can provide more first-class, hardware-supported display outputs. As far as I can tell, no Mac based on a plain M1 chip can drive more than two displays (total), and on the 13" M1 MBP, one of the chip's outputs is reserved for the built-in screen, leaving only one for an external display.

There are workarounds using DisplayLink (not to be confused with DisplayPort!) and similar technologies. These can let you attach more displays, but can involve compromises such as

• Lags
• Unsuitability for applications involving rapidly-changing video content (video editing, gaming)
• Inability to play DRM-infested video from commercial movie streaming services
• The possibility that if a future macOS update breaks the workaround, you will be dependent on a third party to update their drivers to fix things

If you get any DIsplayLInk-based product, you may be directed to the Synaptics site for the necessary drivers and for technical support FAQs.

Synaptics – DisplayLink Graphics

ukpitbull wrote:

Thanks for the quick reply. So it's a limitation on the MacBook side. I'm guessing you can still have 1 external screen and still use the internal display at the same time?

Yes, one external display along with the internal one simultaneously (with different desktops on the separate displays, unless you choose to mirror them).

ukpitbull wrote:

Thanks for the quick reply. So it's a limitation on the MacBook side. I'm guessing you can still have 1 external screen and still use the internal display at the same time?

Yes.

I believe that in addition to the internal display, and your one hardware-supported external display, you can also have

• One AirPlay display, or
• One Sidecar connection to an iPad

It is a limitation of the Mac. The base model M1 supports one external display, the M1 Pro supports two and the M1 Max supports four (with proper cabling and/or the right dock).

If you are doing ONLY program listings, spreadsheets, stock quotes and other slow to change data, there are some other solutions, such as DisplayLink stunt-boxes, but they require you to make some strong compromises.

You will NOT be doing Full-Motion video on such a "fake" display.

If you need more hardware-accelerated displays than the built-in and ONE external display, and an un-accelerated AirPlay display such as an iPad if desired, you probably need a more capable computer.