Probably just a rumor. You can't use a Dell COA XP label for installation of Windows on anything but a Dell (and usually just within a particular product line). Likewise for HP, eMachines, etc. You can only use those product keys with the comparable set of setup disks, usually "restore" disks, so they're essentially useless unless you happen to have the same or similar model as they were originally designed with. I have yet to see an exception with this, but if someone has one, please point it out to me - I'd be curious to see if there's any OEM's who used a true OEM copy of XP.
OEM versions of Windows can be moved to another computer by simply calling up Microsoft. I've done it many times as I've changed out the motherboard and other hardware in my system. The problem with using the product keys or XP disks from a proprietary source is that they will only work on the specific models they were designed for. So a Dell Dimension restory disk will only work on Dell Dimensions, etc. And you can't take the product key and use it with a standard XP installation disk - trust me, I've tried that on multiple occassions.
The worst they will do is refuse software support, but if anything hardware-wise dies, even though you reinstall XP, you should be fine.
