Windows 7 Windows 7 64bit Upgrade


I have Vista Home Premium 32bit. Can I buy Microsoft Windows 7 Home Premium Upgrade and choose 64bit installation?
Also I have another computer with Windows XP Professional 32bit, so can I also buy Microsoft Windows 7 Professional Upgrade for it and choose 64bit install?
I know that for 64bit install I need clean install and cannot upgrade existing 32bit OS.
 

I dont have problem with clean install. Ok, maybe is VHP 32bit license connected to 32bit Windows 7 upgrade and I cannot use upgrade disc for clean 64bit install. But I know that majority of users use XP Professional 32bit, and I think that Microsoft give oportunity to that users for upgrade to Windows 7, 32bit or 64bit.
 

I know that you cannot upgrade (install) 32bit OS with 64bit OS, thats impossible. My question is, can I buy upgrade license for my PC? If I am correct, upgrade CD's are full working install OS'es, they don't care what OS you have. They check if your previous Windows key is legal in Microsoft database.
So, I have XP Pro 32bit and now I want to buy Microsoft Windows 7 Professional Upgrade for 99.99 bucks vs. 199.99 bucks full version.
So, is it possible to make clean install on my XP Pro 32bit and 64bit hardware with that Microsoft Windows 7 Professional Upgrade DVD? I dont think that this DVD is just upgrade DVD.
If it is just upgrade DVD, than I don't have luck. It propably checks your key (and this key is connected to Win XP Pro 32bit, so you cannot install 64bit Windows 7, only 32bit I presume).

Thank you very much for help and sugestions.
 
Yes, of course you can purchase the upgrade license and do a clean install of a different bit version.

You are correct - the license is different - the dvd's are the same for upgrade or full retail.