The answer will lie in your BIOS as to boot options that are available to you. Boot occurs before the O/S loads, so the ability to boot is not related to the installed operating system. Of course, here you are looking for verification for someone who has done so [USB or firewire]. They will chime in shortly. I wanted to give information that fits most systems. If more general information is useful, please select my Disaster Recover--SOLUTION Link below.