Windows Vista Version Question - Which Is Which ?

I am about to build my new, super megafast to me, rig. An AMD 5600 X2. I am contemplating just taking the Vista dive and I am unclear as to what version I need. Is this the one I need: Microsoft Windows Vista Home Premium with Service Pack 1 Upgrade? Is that a full version? Or is it a version that upgrades over XP? If it upgrades over XP, what are the ramifications of a fresh install? Does it need a legit XP disc, which I have?

Thanks for any input.

 

Common' now - I need to know? Either you Geeks are too Lazy or don't know!

 

Home Premium SP1 is your best bet, if you buy OEM, it'll cost you $120 or less. There are retail upgrade packages for $180 but I don't think you would need that.

OT, you'll like that X2.

 

It was just the word "upgrade" that threw me off. I was a bit confused because back in the day when some newer versions of Windows were sold at a cheaper price in relation to non-upgrade versions. The concept being that you could get a discount if you owned a previous version of Windows. As a security check, you either had to have the previous version of Windows installed or you had to insert an install disk from a previous version of the OS.

I just wanted to be %100 sure before I gave Bill my money!

Thanks.