What monitor is compatible with 2016 iMac? I need to utilize dual monitor.

I have a 2016 iMac Desk Computer/Monitor. I have a 2022 Dell monitor. I purchased the HDMI to USB adaptor. The Mac will not find the second monitor. Due to it being an older iMac, it seems that only specific monitors will be compatible. Please share your experience with me if you use dual monitors with your iMac.

thank you!

iMac 21.5″, macOS 15.6

Posted on Sep 10, 2025 2:10 PM

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2 replies

Sep 10, 2025 4:05 PM in response to BeccaYC

If this is a Late 2015 iMac – whether Retina or non-Retina – there is no way that a "USB to HDMI adapter" will work.


Those iMacs have

  • Old-style Thunderbolt 2 ports, with Mini DisplayPort connectors, that can double as Mini DisplayPorts, allowing the connection of a single external display
  • USB-A (USB 3.0) ports


Daisy-chaining a USB-C to HDMI adapter with a USB-A to USB-C one will not work. USB-A doesn't have the ability to carry video signals. All that a USB-A to USB-C adapter will do is to translate USB protocol. There will not be any video signal for the USB-C to HDMI adapter to translate.

What monitor is compatible with 2016 iMac? I need to utilize dual monitor.

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