iMac black screen on boot
iMac late 2015 Monterey. Just swapped Fusion Drive for ssd and checked that all good with ssd connected by usb. Used Recovery mode to install OS and made ssd the startup disc. As everything was fine, I installed the ssd in the machine and booted and got nothing. Chimes but nothing on screen. Checked display connections and they seem fine. What could it be? (Brightness is not turned down btw) (and I reconnected the Fusion Drive with identical result)
iMac 27″, macOS 12.7