Not sure what is going on.....I have a 2014 iMac 5k retina(base model with 2gb AMD). First time today I am trying to hook this up to an external display (32" HD Panasonic TV) using a Mini DisplayPort to HDTV Cable and no dice. I've tried restarting the Mac and turning TV on and off. Tried using different HDMI ports on the TV and tried using both. As a test I used that same cable into my 2012 Macbook Air and it displays right away. I also then tried a different computer monitor with the iMac using a different Apple thunderbolt to VGA and still nothing. The extend display never shows up under Displays.
Specs
Catalina 10.15.7
iMac (Retina 5K, 27-inch, Late 2014)
AMD Radeon R9 M290X 2 GB
Specs
Catalina 10.15.7
iMac (Retina 5K, 27-inch, Late 2014)
AMD Radeon R9 M290X 2 GB
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