it's realizable for me to use the Windows 7 Profession Upgrade CD to install the 64 bit OS on my computer that presently has Vista 32 bit? I'm just notsure because I've read that if you format your hard drive like you would generally have to in order to upgrade from 32 to 64 bit, the windows 7 upgrade CD will say that you have an invalid product key, and if that's the case it sounds like my only option is to install a 32 to 32 upgrade, but I've read somewhere that it actually is realizable to go from a 32 bit vista to a 64 bit 7 widows.

Can you give some suggestion to fix this problem.