Vista upgrade (from XP home) CD key work with Vista 64 bit?

[pullmyfoot]

I know the normal 32 bit CD key will work with 64 bit (im correct am I?). But I was wondering if the Vista 64 bit CD key will work with Vista 32 bit upgrade OS. Because I have an upgrade CD for the 32 bit version with its own CD key. Im gonna get another copy of the OS so I was wondering if I should get the 64 bit version and use my 32 bit CD with the CD key that comes with 64 bit Vista (2 seperate computers). In that way I have the 64 bit version when i decide to stick more ram onto my sytems but stick to the 32 bit one for now since it has less compatability issues.

[Steve R Jones]

If I had to guess, I'd guess that you can mix n match cd keys.

[pullmyfoot]

You think? Ok thanks. i guessed that too. Anyone else has an opinion?