Current Vista users receive a discount. The full Vista Ultimate upgrade license costs $259, which is what XP users must purchase, while you can get a Windows Anytime Upgrade from Home Premium to Ultimate for $159 direct from Microsoft. There's also OEM licenses running around $189 (regardless of ownership of any version of Windows) if you don't mind it being a clean install only (no upgrading) and never being permitted to change the motherboard.
Hope this helps,
John
Does it cost the same to upgrade from Vista Home Premium to Ultimate as it does from XP to Ultimate ?

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