It depends on the meaning of "external". You can certainly boot from
SATA or SCSI drives that happen to be located outside of the computer
box. The operating system has no way of knowing whether a SATA drive is
inside or outside of the box.
USB or firewire connected drives are a different issue. Theoretically,
it should be possible to boot from such connections, but they might not
be enabled in BIOS or the operating system might prohibit the boot.
One interesting question is whether or not you could boot different
computer systems from the same portable drive. This should work if both
the OS and the application programs are on this drive and the hardware
contains basically the same components (so that the drivers
same). This would work fine with UNIX/Linix. It is hard to say how many
problems might result from Microsoft's DRM. It might require only a
Peter Foldes wrote:
> You cannot boot from any external Hard Drive even if is a USB