Like smorizio mentioned, it could be related to Fast Boot or Ultra Fast Boot. With Ultra Fast Boot you cannot enter UEFI setup in the normal way and you will not see any POSt screen.
In that case you need the "Restart to UEFI" utility to get into UEFI setup, where you can change the setting for Fast Boot. You can download the utility here:http://www.asrock.com/mb/Intel/Z77%20Extreme4/?cat=Download&os=Win864
Or use clearCMOS to reset UEFI o default values.