I just found my Apple DVI to HDMI adaptor and would like to connect my mid-2007 Macbook to my Dell S2722QC 27-inch 4K USB-C Monitor which has 2 HDMI ports.
I plug everything in and the monitor doesn’t acknowledge any HDMI input (and checked I’ve selected the right input :)
I poked around the net and the best I found is one unanswered thread and a response in regards to changing the HDMI mode (which I’ve looked through all the menus on my Dell, I don’t see a way to do this)
While it’s been awhile, I seem to recall in OS X that you had to use Fn-F7 to enable DVI out (ie. it wasn’t on by default) - is there an equivalent hotkey in Elementary to enable DVI out by chance?
EDIT: I rebooted into OSX 10.11.6 and it mirrors to HDMI immediately - no hotkey required. EDIT2: I got a previous build of Batocera (v26 May 2020) which is Linux-based (busybox) to boot this MacBook. I was able to, in its video configuration menu, select DVI output - so it is definitely possible to do this from Linux!