The obvious question:
Have you gone to the computer manufacturer's website and looked for anything there?
While I speak from a great deal of ignorance about the subject, this looks like it explains the situation a little.
http://www2.geek.com/discus/messages...tml?1143232644
As a matter of interest, when I had a (non-HP) motherboard die, I experienced some problems with Windows installation, to the point that the store where I bought the mobo helped me with the install. They also accidentally left an HP OEM Windows CD in my computer. I offered it back to them (after I duped it) and the tech told me it would install XP Home on any computer, but it would copy a few drivers specific to HP onto my computer. He was right. I've used it a couple of times now, the only catch being that I have to activate XP with Microsoft. I just type in the number off the label that came on my computer, and all is well.
As far as I know, that doesn't constitute piracy, since the computer originally came with XP Home. Microsoft doesn't seem to mind, amazingly enough.
I don't know why this install CD doesn't look for a tattoo. As the article said, Vista apparently makes things even tougher.