flash BIOS to version23:
First, unzip the package to root directory of a udisk, then connect the udisk to the machine;
Second,Power on to press 'F2'to enter setup, choose 'Security' menu, change 'Secure boot' to 'Disabled', then press 'F10' to save and exit, choose 'EFI USB Device' to boot;
Third, it will automatically flash BIOS, then reboot, Done!