Hence my statement "in the vast majority of cases." Unless, of course, you're implying that replacing your motherboard is a frequent occurrence. I've never had a problem with BIOS upgrades in terms of activation.
Seeing as the motherboard is the most basic (and least likely to be replaced) component of a computer, replacing it makes it seem to the software that it's on a different machine.
I replaced my motherboard recently and all that happened was it asked me to reactivate, and it only took 5 seconds with a couple of clicks.
PS: I was using XP. I haven't yet tried reactivating Vista.
Not even in "the vast majority of cases." Just because you haven't had problems doesn't mean
Most of the computers in my house are running with upgraded hardware--and each time required a call to MS to reactivate.
This is one reason why I try to do most of my work on Mac or Linux. If something should happen (which on those systems rarely does), I at least have the ability to reinstall my OS without having to talk to overseas Tech Support for three or four hours.
And SuSE is horrifyingly easy to install (my 13 year old brother can run the install (including partitions) for me without a problem if I'm away at work or school)...
That's the point.