u/Fredric444

I used existing display and hub hardware to configure 6 displays on my Macmini M4. It is stable and userful for multiplatform software development plus general multitasking.

Notes:

• I have the needed ports via CalDigit and Plugable T4 / USB 3.1 hubs.
• Basic Strategy
  • Thunderbolt 4 for high-framerate. I have one monitor running at 240Hz via T4.
  • iPads: Sidecar for first iPad and Duet Display for second iPad. Sidecar will only drive 1 iPad monitor. Bonus, Duet Display supports older iPads as external monitor when iPad is not up to Sidecar spec.
  • Additional HDMI monitors: DisplayLink (USB). This is a protocol which is built into some USB monitors. Alternatively, buy a cheap dongle with multiple HDMI ports (I have tested GiQ-brand and Plugable-brand).
  • Sidecar, Duet Display, and DisplayLink can all operate concurrently.
• Not a gamer, have not tested gaming performance with Sidecar, Displaylink, or Duet. 60Hz video playback/editing is fine on all monitors, including 4K.
• Yes, there are other ways to do this. This is what I had on hand, hope it helps someone.
• Plz don't hate on my cabling or hanging t-shirt sunshade.

1 x HDMI direct + 2 x HDMI DisplayLink + 1 x Thunderbolt + 1 x Sidecar (Pad Air Gen 5) + 1 x Duet Display (iPad Air Gen 3)

iPad Air Gen 3 (lower right) does double duty as both desktop extension under MacOS, and \"Linked keyboiard and mouse\" under iOS. The latter is what shows as the slightly detached 7th display in the MacOS arrangement.

Screenshot of the iPad Air Gen 3 running the Duet app. To use it as a extended desktop for MacOS, just select the Duet app. To use it as an iOS device with keyboard and mouse extended from the desktop, switch to any other iOS app or iOS desktop.

iPad touchscreen can remain active when running Duet to show MacOS extended desktop, which is kind of cool.

DisplayLink driving 2 x HDMI monitors via cheap USB 3.1 dongle.