The oldest physical box in the house, a 12 years old Core2 Quad in an old case was my Windows 10 box, nutmeg, which I don’t use very much except to test out various things under Windows. I don’t do much with Windows any more, yet it was attached to one of the three monitors on my desk – using up 1/3 of my total screen real estate; and it was generating heat and fan noise, and its presence offended me. I decided it needed to move to the basement, alongside Cinnamon and Rosemary who are already down there in a rack — banished to the basement because they have a lot of disk drives, and so generate a lot of heat and noise.
I bought another rack mount chassis, and moved nutmeg’s innards to it. This proved annoyingly difficult because various old bits of hardware decided this was a good time to give up the ghost – I lost two old disk drives that decided to stop functioning. But eventually got everything up and running.
The idea was that I would manage the box, on the relatively few occasions I needed to do so, just as I do both Cinnamon and Rosemary, with a VNC connection. So after it was up and running on my work table, I pulled the monitor, keyboard and mouse and rebooted. But attempting to connect with VNC failed. For the record, this was TightVNC.
I eventually found that VNC would work if and only if I had a monitor attached. Furthermore, if I had a monitor attached and established a VNC viewer to nutmeg, if I then unplugged the monitor the VNC viewer would immediately freeze. WTF?
Without making this a long story, I found that the problem could be resolved by changing an option in Settings/Accounts/Sign-in options which is down at the bottom under Privacy, and reads “Use my sign-in info to automatically finish setting up my device after an update or restart.”
So my mental model of what is going on is that if that option is set, windows is attempting to “set up my device” and I suppose the device it is trying to “set up” must be the monitor. What I don’t exactly get is why the VNC viewer should freeze when an existing monitor is removed. I suppose that removal generates some event internally, and processes attached in some way as consumers must be killed or something. Not sure. I don’t need to understand it. I have very few cycles in my advanced age and am not planning to waste any of them trying to figure out Windows.
I was very pleased that after I did this, and was able to connect via VNC, I was able to set the resolution to various values up to 4K. And after rebooting and reattaching it even retained my display resolution setting.