Hi everyone I need some advice from the experts here I have Vista Ultimate (both 32- and 64-bit DVDs) and have never used it, so obviously it hasn't been activated as it's never been installed. Can anyone tell me the cheapest way to get Windows 7 64-bit? I understand I can install Vista Ultimate and install a version of Windows 7 over the top, but I'd rather do a clean install of Windows 7 if possible - Windows 7 Home Premium 64-bit would be fine. I have absolutely no interest in Windows 8. What's the cheapest way for me to do this? Is it possible for me to "trade-in" my Vista disks for an equivalent version of Windows 7? I remember many years ago reading somewhere that when installing an upgrade Windows only looks for a specific file. Is this still the case? And finally, would I be able to use one of the OEM Windows 7 versions I've seen on Amazon? I'm in the UK by the way. Many thanks in advance.