I'd run the upgrade tool first, here, and run it without buying Win 8. It will give you the info. Pro upgrade is £49 from Amazon but you might find it cheaper elswhere. I'm running Win 8 32-bit on an old laptop that has a 1.7 Ghz CPU and 2 Gig ram so you'd need to get more ram I think. Also check if your XP version is running 32 or 64 bit as you'll need the same version of Win 8.
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