Microlith writes "Microsoft has updated their WHQL certification requirements for Windows 8, and placed specific restrictions on ARM platforms that will make it impossible to install non-Microsoft operating systems on ARM devices, and make it impossible to turn off or customize such security.
Choice quotes from the certification include from page 116, section 20: "On an ARM system, it is forbidden to enable Custom Mode. Only Standard Mode may be enable." which prevents users from customizing their security, and in section 21: "Disabling Secure MUST NOT be possible on ARM systems" to prevent you from booting any other OSes."
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