H170M Pro4 fake boot

I've just finished assembling the following build:

• ASRock H170M Pro4


• Intel i3-6100


• Crucial 8GB DDR4 CT8G4DFD8213


• Samsung 850 EVO M2 MZ-N5E250BW


• Be quiet! System Power B8 300W

No discrete VGA or other PCIe cards. Running everything at default, stock speeds, etc.

The system runs fine, boot the OS without problems and it's rock-solid.

BUT

If I unplug the system (ie if I turn the power suplly switch to off), at the first following start the system will power-on, fans spinning for about two or three seconds, then power-off and then power-on again on it's own this time booting regularly.

Seems like the fake boot of old P965 board when overclocked.

If I leave the system always connected, no problem at all.

What can it be? UEFI updated to 7.10.

Thanks for any suggestion.

Bye

The Wake on LAN networking feature, when enabled (enabled by default) must do a reset after power is removed from the board.

It's not a fake "boot", it's a partial POST. The OS does not begin to load at all when that happens.

Also, it is still common for modern boards to shut off in some circumstances after applying over clock settings to the CPU or memory, and saving and exiting the UEFI/BIOS.

Happy to help, enjoy your system