Nope. Just buy the upgrade version. The first time it asks for your product key don't enter it. Select the version you purchased then go on with the install. After your install completes go into your computer select the upgrade vista option. It will ask if you want to upgrade or do a custom install. Do a custom install which does a clean install. This time when it asks for the product key enter it. After install finishs go ahead and activate vista and your good to go.