Vista på Mac

Hi
I would like to buy parallels and run Vista home Premium (OEM) or does it have to be retail version. I have also read that Microsoft have released an upgrade for Vista and now you can only run Vista Ultimate in Parallels. I will be buying 2 copies of windows so it can become a little expensive if I cannot use them.

 

You can use every Vista edition in Parallels , unless they are OEM versions

 

So you cannot use OEM versions of Windows Vista