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iMac not recognizing external monitor

Anyone having issue with connecting an external monitor? I have an iMac that I want to connect to an HP Pavilion monitor. I am using a Thunderbolt 3 to Thunderbolt 2 connector which plugs in as HDMI to the external monitor. External monitor does not seem to receive any signal and goes to sleep.

iMac 27", macOS 10.15

Posted on Mar 20, 2020 3:31 PM

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Posted on Mar 20, 2020 4:42 PM

The Thunderbolt 3 to Thunderbolt 2 adapter won't work with non-Thunderbolt displays.

If your computer has Thunderbolt 3 and the display has HDMI, you need a USB-C to HDMI adapter or cable, such as:

https://www.startech.com/AV/display-and-video-adapters/usb-c-video-adapters/usb-c-hdmi-cable-2m~CDP2HD2MBNL

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Question marked as Top-ranking reply

Mar 20, 2020 4:42 PM in response to jfrench012

The Thunderbolt 3 to Thunderbolt 2 adapter won't work with non-Thunderbolt displays.

If your computer has Thunderbolt 3 and the display has HDMI, you need a USB-C to HDMI adapter or cable, such as:

https://www.startech.com/AV/display-and-video-adapters/usb-c-video-adapters/usb-c-hdmi-cable-2m~CDP2HD2MBNL

iMac not recognizing external monitor

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