We have device with follow configuration:
All the scheme consumes 12V directly and 12V separately for other devices.
The problem is: Windows IoT some times not loading, presumably because of monitor power consuming.
Is it possible to configure programmatically or via Windows Device Portal to load HDMI after Windows IoT is loaded?
First, to determine if this issue caused by HDMI. You can check if this issue caused by HDMI via disconnect the HDMI to see if the system can boot up every time. (Use Windows 10 IoT Core Dashboard application to find its IP address. Via ping its ip address or device portal to see if the system has booted up.)
If the system can't boot up when you attach the HDMI pad, you can supply the power for HDMI pad separately. There is a power supply port, something like this: