@sawkward that was my first port of call, got a spare cable from a friend, and it works as long as it isn't plugged into the HDMI port on my desktop (the current monitor is an HDMI cable to a HDMI>USB adapter into USB since I only have the one HDMI port.
I've tried updating drivers, swapping cables and everything around, and I can only come to the conclusion that the HDMI port on my computer is fucked somehow, despite being INCREDIBLY careful with it during this move.
@Smutty_Tiefling I ment this one it gives you the option to add device and may come up in the list. Alternate but costs money is picking up a cheap graphics card tat will give you multiple hdmi slots
@sawkward took me a minute to navigate to that screen #FuckWindows11 Except NOW my second monitor is no longer giving me "No Input" but "Cable not Connected" errors.
Same cables, both still work just fine if I plop 'em into the USB adapter.