>I'm seeing quite a few XP Pro for sale on eBay, but many say they are OEM. I know what that means, but how can I know that I'm getting the box version, not an OEM? Is there also a way to know whether the version on my PC is OEM or not? I positive it is not, but I want to be dead certain before I shell out $130 for it because from what I've read, you can change the key to the existing OS, but only if they match the current version of OEM/Non-OEM.

The question mark in the title can probably be replaced with "same old equipment manufacturer", I guess. That'd be a good opposite for "original", and would merit a "vs" between them.

There would probably be a lot of contenders for the right side, but they'd be hard to find, as they never advertise as such.