Brian Wescombe said:
Does a dual-core processor count as one or two processors for the
Vista Premium licence? Or would dual-core machines require Vista
Ultimate?
Best way is to think of it is the number of sockets on the mother
board.
The current licensing is on per CPU package basis - as in the thing
that plugs into the CPU socket on the motherboard.
The number of cores as relevant for dual and quad core packages or
pseudo processors as relevant for the hyper threading CPUs are not
counted. So if you are purchasing an OS licensed for "two CPUs" you
are currently licensed for 2 sockets, irrespective of what is in them
in terms of internal cores or functionality of the CPU.