New
#11
I have a Dell XPS. It came with Vista, 32-bit.
As a test I grabbed a x64 version of Vista SP2 (from MSDN) off of Usenet and did a clean install with it. If I'd pleaded I think Dell would have sent me one. For the cost of shipping MS would have sent me one.
I entered the serial that came with my Dell.
Windows made me go through a phone activation (you alternate entering info on the phone and your PC) but it did eventually recognize my system as legitimate.
YMMV.