Hi, Here in the UK I can pre-order Windows 7 Home Premium or Professional for Ã‚Â£30 (inc VAT and delivery). I can also pay Ã‚Â£9 for a disc as opposed to a digital download. I want to do this, but the disc is an upgrade disc, so I'm wondering what you'll need to perform a clean install. I have genuine copies of XP Home and Vista Home Premium, but if I do a clean install, how does the upgrade disc know this? :S I remember with Windows 98 you had to insert a Windows 95 disc to prove you had it, but today I can imagine that this would be too easy for pirates! I have the disc for Vista Home Premium to go with the code, but not for XP Home. I've read the stickies, but they were about upgrading, whereas I want to do a clean install! Thanks, Thomas.