But I very much doubt that they would be overly affected by doing this though here if there is no COA on the case at all I would question the Authenticity of the XP License. It sounds very much like a Pirate Copy to me.
2 years ago many Computers where purchased with the Vista OS and could be supplied Loaded with XP depending on the customers preference. In those cases the system came with a Vista COA on the case and a Vista Recovery Partition/Disc Set and you could request XP Install Disc's for when you needed to reload/repair the XP OS.
As for OEM you can replace Data Leads, HDD's or add more to Desktop Systems, Optical Drives. RAM and so on without needing to purchase a new License. However if you Upgrade the M'Board to increase Performance to a considerably better CPU you should buy a New Windows and other M$ Software License. But this is where it gets difficult if you where to repair a computer by replacing the M'Board & CPU with a [b]Current[/b] Low End CPU you can stick with the Original License.
As for buying a New Upgrade License to 7 it should look at all the installed Drives and find the required XP Files or even the Vista Recovery partition if you have a Legit M$ License and complete the Install without problems.
As for M$ wanting to complain I very much doubt it as they are getting something in the form of a 7 License Fee that isn't specifically required by their Licensing Agreement so I can not see them being overly concerned that you want to pay them to upgrade to 7 from your Installed XP Copy.
But before you even start to consider this option you should check your Hardware & installed Software with the Windows 7 Upgrade Adviser available here
http://www.microsoft.com/downloads/details.aspx?displaylang=en&FamilyID=1b544e90-7659-4bd9-9e51-2497c146af15
At the very least you should know what you need to replace or what will work with 7 before considering anything at all. ;)
Col
