So the pre-boot state is before you turn PC power on, and you do not want that if the monitor does not also have another input than USB?
This monitor that required USB C turned on fine from boot with both power and signal from USB.
No, by "pre-boot state", I mean anytime prior to the O/S (i.e. Windows) taking over control of the hardware. Windows has support for using USB-based monitors. The BIOS, however, does not. If you use a portable monitor that is USB-based (I am talking specifically about its graphics output capability), then you will not be able to "see" BIOS initialization or be able to enter BIOS Setup to make configuration changes (the monitor would only start operating once Windows was loaded and running).
The monitor you have shown is fine because it is using the DisplayPort output that is available via the USB-C connector (and is not doing any output via USB itself)
Okay. But I can confirm that these
Intel® NUC Kit NUC7i3BNH
ASUS MB16AC FHD USB Type-C Portable Monitor
show the BIOS setup excellent using only one USB cable and without any other screen connected to the NUC. The monitor can be used either with USB A + driver or USB C, and since NUC NUC7i3BNH has USB C, the USB C cable from monitor needs no adapter. Only concern about the monitor is, that it´s stand uses magnets, that might erase some data storage near.
The monitor has got a darkscreen setting that reduces its radiation well. And likewise the NUC has a disable WiFi setting that turns off the electromagnetic problem - that else adds up with other similar radiations to cause cancer.
The devices was bought with 2 x hyper X 16 GB ram. Installing them were like magic, because they had to be inserted without being touched, and it worked?!
Also 2 x Samsung EVO 250 GB SSD were bought.
Perhaps two parallel memory blocks give CPU capability to read and write simultanously with RAM? But two different storages are certainly better, since it allows data copies seperate if one should fail. Still the Space for the large SATA SSD (not the M.2) might be better used as place for battery - and portability.
The NUC power for the whole PC were reasonably light. But why do simcity developers still build houses with high voltage that require transformation, so practically all devices need heavy transformers in carrying weight? It is just an excuse to build cars to travel in with all that extra load.
Legacy boot in the BIOS wasn´t much worth, since NUC NUC7i3BNH has no USB 2.0 to support keyboard or mouse during Windows 7 installation, that has not been updated to support USB 3.0.
UEFI Windows 10 installs well, but requires a ton of customization - especially "internet is not yours - so keep your fingers away!"