Computer Upgrade Kit

Which version of Vista do I need to purchase if I am building my own computer?

I already have my installation disks for XP, so I plan on installing that, then upgrading to Vista. Do I only need to buy the upgrade kit for Vista then?

you`ll have to buy the full software disk of Vista.
it`s quite expensive. try finding the Vista Home-Premium, its one of the cheapest, and have some interesting features like the Windows Aero.

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