I called up MS Support earlier today to ensure that I fully understand what I can and cannot do. I have an OEM version of XP on my home-built system that is activated and registered with Microsoft. My motherboard is failing so I need to replace that and the CPU at the very least. This renders my OEM XP useless.
I enquired about re-registering/re-activating my OEM XP when I get my new motherboard. I was told an interesting list of 'facts' by the MS support person:
1. I shouldn't have had an OEM copy in the first place.
2. The OEM copy is for registered system builders only. It is not to be sold to end users.
3. The OEM copy is for one-use, one-computer only. If the hardware fails then OEM XP needs to be repurchased.
4. I should be using a retail copy of Windows XP.
5. If I changed my motherboard then it is recommended that I purchase Windows XP Professional Retail Edition.
Now, this is very disappointing so i'm hoping someone can clarify some of these points and what the best option for me is.