At least part of the reason is not technical, but philosophical. See the third item in the FAQ https://secure.raptorcs.com/content/base/faq.html https://secure.

At least part of the reason is not technical, but philosophical. See the third item in the FAQ https://secure.raptorcs.com/content/base/faq.html https://secure.raptorcs.com/content/base/faq.html These CPUs are completely open and "free". In addition to the libre philosophy this guarantees a level of security unobtainable with any other CPU. The same rationale is behind the powerpc laptop project https://www.powerpc-notebook.org/en/ https://www.powerpc-notebook.org/en/