For the Dell OEMs XP, it actually works on all Dell hardware, old or new, without the need to activate, or even insert CDKey.
The certs are in the WXP cd already. So, all it needs to detect is the BIOS SLP string. Yup, indeed. 30 days thingie can be seen at your system tray. But if the cd is used on the same brand either notebook or desktop, it should work.
i obtained my copy on line(if you know what i mean ) and it seems to work without any problems. i have added more memory to it and i never got a reactivavate warning. i will get a legit copy when i am forced to do it but only after it is semi stable so till then i use it as my beta drive to see if i like it. xp is still my main os, and i paid for it.