NUC9i7QNB (Ghost Canyon): Disable/change bios splash screen

[Horent4711]

On every start I only get the plain "Skull" splash screen, with no further messages. 

Even when I activate settings in bios like "press F2 Key for Bios setup" etc., there is no message like that during boot. 
What I am missing to get common POST messages during boot on my Ghost Canyon?

Best Regards

[LeonWaksman · Accepted solution]

This menu (F2, F7, F10,..) is not displayed since Secure Boot is enabled. Disable the Secure Boot in BIOS and the you will see the POST Menu. I don't know why it is done this way and in the past I've have even discussion with Intel, but never get reasonable answer, except "...this was Microsoft request". I don't understand what is beyond such request. However, I want to mention that even the Secure Boot is set and you can't see this menu, the "F" keys are responding (i.e. F2, F7, F10)

Leon