I have a Philips 190SW VGA monitor which, while it cannot display a super resolution, it can be a descent second display for things that you need, yet they do not need to grab your immediate attention. So I got a USB-C to VGA adapter and hooked it up.
Sure enough Windows 10 recognized the monitor and I arranged the displays to my liking and was very happy. Only there was a problem. After the power saving mode kicked in, Windows lost the monitor. It could never figure out that it should come off the power saving mode when I started working again. The quick, yet not very practical, solution was to unplug and plug again the USB-C adapter.
Searching the Internet I saw that I am not alone in this issue and the proposed solutions vary and seem like random shots in the dark. There is even at least one adapter by StarTech offering a presentation mode claiming that it never allows the (VGA) projector to go to sleep mode. And the best hack I found (sorry, I’ve lost the reference) that suggested:
> In my case, one of my VGA monitor’s was connected to a VGA to DVI connector going into my graphics card. I simply pulled PIN 12 from the VGA cable going into the VGA to DVI converter, problem solved. Monitor does not go into Power Savings mode, shown as Generic Non-PNP monitor in Device Manager. The signal for Auto Detect/PNP is not transmitted through to the VGA to DVI converter and the problem is gone!!!
Short before actually going through with this, I decided to boot to Linux (Ubuntu) and see whether the behavior gets replicated there. It did not! Bang. So it must have something to do with how Windows handles the monitor. Rebooting back to Windows, I fired up the Device Manager and went ahead and updated the monitor driver to …
Generic Pnp Monitor. Success!
If you’ve scoured through the net for this very same problem with no solution, then this post might help you out too.
PS: Sometimes, even the above trick does not help. In those cases it seems your only alternative is to disable turning off sleeping your screen altogether, and just set a screen saver.