I have an ASRock H170 Pro4 updated to latest BIOS (2.30). I use Windows 10 Pro 64 bit, updated to latest patches.
The problem is: when I shutdown (or restart) from Windows, the pc remains active, with black screen on the monitor.
I have already tried disabling "Fast boot" from Windows 10 options, but issue still remains.
I tried updating BIOS (in this case, the motherboard correctly restarts itself), resetting to defaults and changing deep sleep mode with no effects.
I use a Samsung 840 Evo, so I tried disabling also RAPID mode and activating/disabling hibernation.
Any ideas?

My PC components are:
-ASRock H170 Pro4
-Corsair Carbide 200R
-Corsair CX 550M
-Intel i5 6500
-EVGA GTX 750 Ti
-Samsung 840 EVO 120GB
-other 4 HDD