Quote Originally Posted by DavidY View Post
Quote Originally Posted by Phone Man View Post
You can do a clean install of windows 8 with the Upgrade version but takes an extra procedure to activate.
If you install on a PC with a running version of Windows 7/Vista/XP then as long as the old version is in place on the disk when you start the installer, you shouldn't need to do anything extra to activate.

It's still a clean install because you can wipe the partition from within the installer.

I've done this a few times and it's always activated automatically for me.
What the OP wanted to know, If he buys the Upgrade version and in the future need to reinstall to a clean disc. That is what the Tutorial covers.