Hi, read this part of the manual: https://www.udoo.org/docs-x86/Hardware_Reference/UEFI_Firmware.html Also take note of the warning: If you get a black screen when you try to enter in one of the UEFI Firmware Setup Utility Menu options, try using another Display (HDMI or DisplayPort) or a different cable.
Thanks waltervl for you comment! I finally try out this procedure to go into BIOS setup: Press "Esc" immediately after power-ON to go into Udoo x86 front page -> then click on SCU to enter InsydeH2O BIOS setup utiltiy
Sometimes you might just need to hold the Esc key until it pops up. You might not see it if the monitor doesn't turn on in time.
This is the reason why I set a 5 second delay for the splash screen so that I have time for the monitor to wake up and for me to decide if I want to access the bios or select a boot device. I even enabled display of which Fn key to press to access the boot manager, bios, etc instead of selecting it from the GUI.
plus, an udoo splashscreen is cool I was missing it on my x86 since i come from Udoo Quad but sadly they are unscreenshootable