Additional notes:
* When I enable the HDMI port, I used --mode 1920x1080 --scale-from 2840x2160
* I have just discovered that I _can_ reenable the DP using nvidia-settings, but ONLY as a mirror-of or BELOW my existing laptop screen. What I cannot do is make the DP screen be ABOVE my laptop screen. It's as if using the HDMI port (with scale-from?) has locked the laptop screen to X coordinates (0,0).
Additional notes:
* When I enable the HDMI port, I used --mode 1920x1080 --scale-from 2840x2160
* I have just discovered that I _can_ reenable the DP using nvidia-settings, but ONLY as a mirror-of or BELOW my existing laptop screen. What I cannot do is make the DP screen be ABOVE my laptop screen. It's as if using the HDMI port (with scale-from?) has locked the laptop screen to X coordinates (0,0).