Technophiles like ourselves who are also frugal have, in the past, purchased upgrade editions of Windows, and been able to do a clean, fresh install either by entering a prior valid license key or inserting a CD for the older software at install time. That went away with Vista, which required a hacky workaround, but now Microsoft is completely shutting down even that methodology, for Windows 7. Why the big deal about a being able to do a clean, fresh install with an Upgrade edition? If you install an upgrade