I recently upgraded major parts to my desktop PC, which originally had an OEM version of Windows XP Professional installed. However, I was running it at 32-bit, and with the new hardware I've also upgraded to 64-bit, and am now running Windows 7 RC instead of the Windows XP OEM. I've read a moderate amount of threads and articles about the specifics of the upgrading requirements for Windows 7, but I couldn't seem to find an answer to my situation, which is a bit more specific. (There are also a lot of various answers floating around, and it's hard to tell which one is more credible...) Would I be able to purchase and use a Windows 7 Professional Final/RTM upgrade ($99) on my new machine, which currently has Windows 7 RC as the OS, and use my previous Windows XP Pro OEM license key to validate it? I've read some articles stating that I would actually have to have a valid copy of Windows XP installed prior to upgrading to Windows 7. I've also read thiings like, only being able to upgrade to 32-bit Windows 7 if my previous XP was 32-bit, and all kinds of other thiings. I don't mind doing a clean instal, at all (in fact I would prefer it) - I just mostly want to know if I can purchase the $99 Windows 7 uprade or not. (Basically, looking to make sure that I have a valide upgrade path here...) Thanks for everyone's time! Any advice is greatly appreciated.

mandarinmoxie - Just to make sure I've got the story straight - you had an older computer that came with XP Pro preinstalled. You've now upgraded the hardware inside the box and have installed Windows 7 RC 64. You want to know then, if you can reinstall the XP Pro 32 bit and upgrade to Win 7 Pro 64 come October 22nd (or thereabouts). In a word - probably not. Just as a test, I inserted the 64 bit Vista upgrade dvd (which runs a similar installer to Windows 7) and the autorun program coughed up an error saying it could NOT be run on my 32 bit OS, please boot from the DVD and run setup from there.Of course, in order to do an upgrade, you have to run the installer first from the OS to do a direct upgrade - even if it winds up being a clean install.Now then, there IS a means to do a clean install from an upgrade disk in Vista and the procedure will likely work with Windows 7 as well. But given the nature of said procedure, discussing it here could be classified as being a bad thing - so you'll have to search the web for it. I don't see a conflict in this case - as long as your 32 bit XP Pro remains permanently retired.

If mandarinmoxie's computer came with an OEM reinstall disk (or restore partition) it should be possible to run that and have 32-bit XP Pro back for the upgrade disk to see...or am I missing something?

The thing about OEM disks (or restore partitions) is that they come activated, at least they do on store-bought systems; I'm not sure about OEM disks purchased separately. So if mandarinmoxie's computer is store-bought, running the reinstall disk would produce an already-activated Win XP Pro 32 for the Win 7 Pro disk to "see". It might produce difficulties if XP Pro were to keep running, but should be sufficient for installing Win7 final.