With Vista appearing prices for used WIn XP versions have dropped a lot, you get these very cheap right now - so i would not base my purchase decision on the included OS. After all you buy a computer system, not an operating system. I have used the XP from my old computer (the old one died) as a secondary installation, because the new system had Vista pre-installed. I also had many problems with Vista and would also recommend XP. I couldnt get older 3D Studio versions and other software working on Vista at all.

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