The PC hangs forever after displaying the following two lines:
Intel(R) Boot Agent GE v1.3.27
Copyright (C) 1997-2008, Intel Corporation
Pressing the keys usually bound to BIOS or UEFI functions (F2, F12, Del...) before or after has not effect.
The keyboard seems to be stuck, pressing Caps Lock or Num Lock does not change the status of the corresponding status LED.