Thanks LB. Good link

I think MS needs to update some of their documentation as that is another page which states nothing about transferring System Builder licences. This is why I've never bought one and only bought retail products (licences). They should state that their are two different types as Roy mentioned.

"OEM keys are not-for-resale and may not be transferred to another computer. They may, however, be transferred with the computer if the computer is transferred to new ownership."

Placing that statement just under OEM system builder doesn't make it clear that some are transferable to a different PC. Makes it sound like they have to stay on the same PC but can be transferred to a new owner.