Only one external monitor at a time is working.

Brand new desktop, M3 chip, two USC C ports. Whichever monitor is plugged in first, works. The second one will not work. Tested both independently and they work.

Any advice?

iMac (M3, 2023)

Posted on Feb 22, 2024 8:51 AM

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4 replies

den.thed

Level 10

94,850 points

Feb 22, 2024 9:01 AM in response to jspegel

The 2023 24" M3 iMac only supports one external display.

see "Display Support" at > iMac - Technical Specifications - Apple

and > Connect an external display to your iMac - Apple Support

Feb 22, 2024 8:59 AM in response to jspegel

This is correct. The iMac only supports one external display.

click here ➜ iMac - Technical Specifications - Apple

hcsitas

Level 6

13,970 points

Feb 22, 2024 8:56 AM in response to jspegel

“Works as designed”: Only one external monitor is possible.

Allan Jones

Level 10

81,110 points

Feb 22, 2024 9:02 AM in response to jspegel

The tech specs for that model tell the story:

iMac (24-inch, 2023, Two ports) - Technical Specifications

specifically this:

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Only one external monitor at a time is working.