Not the only reason, just one of many reasons why OEM is cheaper than
retail.
There is nothing in the license that refers to the motherboard.
A fried motherboard replaced is an upgrade/replacement and you can do
that with OEM.

--
Jupiter Jones [MVP]
[url]http://www3.telus.net/dandemar[/url]
[url]http://www.dts-l.org[/url]


"***** charles" <me@mine.com> wrote in message
news:9V5Ti.15683$JD.15482@newssvr21.news.prodigy.net...[color=blue]
> With Retail if the computer goes belly up you can install it on
> another
> computer (one at a time). With OEM if the computer/motherboard
> dies the licence reverts back to Micro$oft and can't legally be
> installed
> on another motherboard. That's why OEM's are cheaper.
>
> later.[/color]