Those OEM / System Builder things aren't limited to places like Dell and HP. I believe they're normally what you'd buy if you're building a computer and selling it to someone else. You then become the support staff for the OS -- Microsoft doesn't provide it. Unlike the normal licenses, it also gets tied to that one computer. You can't move it to another one later. It indicates stuff like this in the description on that very page. I do think I read at some point that the restrictions for the OEM versions may be more lax in the EU (e.g., you might not have to be reselling the system). Anyway, it would work on a software level for anyone's computer, but there are going to be slightly different things with activation and transferring, etc. Don't confuse them with the way the big OEM's like Dell and HP do things though.
yes, it works, u have your own key. the OEM version has to be sell with any piece of hardware, normally, even a mouse, except they sell it without any piece of hardware. i bought vista ultimate OEM. got one key. there's no offline activation like dell or HP. it's just one OEM DVD for one system with one key, online activation.
This is the short and simple part if you are not using the OPK to install the OEM copy of windows and reselling it then you can't legally use a copy of OEM. OEM is not in any way for personal use and is only to be sold with a new system using the OPK to install and resell the system. Does this mean it won't activate and behave like a normal copy of Windows? Oh course not it just means that you saved some money and navigated to one of those gray areas of Windows licensing. Uncle Bill is not going to come to your house and arrest you, nor will your copy ever be flagged as non-genuine because you failed to use the OPK to install your copy of Windows. If you want to be 100% legal and legit according to US licensing agreements (this means your country may be different, yes I am looking at you EU and Germany), you have to buy retail or get a copy through technet or a student discount etc. OEM is not legally allowed to be used without being installed using the OPK then resold (of course you could just use the OPK to install then sell the machine to yourself, then reformat the machine yourself and reinstall fresh, confusing yes but it is legal and allows you to buy an OEM copy, OR you can just avoid all that buy an OEM copy and install the damn thing normally and nobody will know the difference).
It mainlay depends on thy country you live in. Here in germany usually ONLY OEM aka System Builder Versions are sold in the stores - Retails are the exception cause they cost much more. A major german court decided thats its legit to sell and buy OEM/SB Versions. The only differences are 1) you don't have 2 MS support calls for free and b) you get only one install media - 32bit OR 64bit. But the key with the SB Licence is valid for both architectures and last 3) you can't activate them by internet, you have to call a free hotline and interact with an computer voice. As far as I know this counts for the whole EU.