The drive also holds a full, licensed and verified copy of Windows XP Pro.
Assuming the computer this drive is coming from had a hard drive in it with a bundled, pre-installed, copy of Windows XP ....
It is only "full, licensed and verified" for the computer it came inside.
Take it out of the computer and it becomes unlicensed, and technically Microsoft's considers attempts to use it in another PC as a form of software piracy.
See question 10 in this document
http://download.microsoft.com/downlo...42/OSLicQA.doc