Originally Posted by JadeMiner
Unless Microsoft has changed it's policy. Each version of XP (OEM OR retail) is locked into the hardware configuration of the first computer that activates it. It uses a points system. Once too many of the pieces of hardware are changed (like a different computer, or a motherboard CPU ram upgrade) it triggers the CD Key NOT to allow activation on that computer. To say a retail version of XP can be activated with the same CD Key on ANY computer after being activated is simply not true.
That has always been the case more or less, but there is a very large difference between the two.
With a retail XP, you could sell it on the street, and they could reactivate and use it legally.
With OEM XP, you can only install it on one machine, and can't ever use it on a different one. Basically once you trip the hardware change thing, you have to buy a new OS.