Essentially there is no practical limit. The license specifies only that you
can install a single installation to a device. The "device" itself is not
specified as any particular piece of hardware, so if you swap out parts for
newer ones on occasion you will be able to reactive (by phone generally,
which can be time consuming) as long as you don't install with that license
to a second system. There's a lot of leeway built into it when it comes to
the definition of it being the same system.

The intent of the OEM license is that it is tied to the original hardware it
is installed and activated on, but in practice it doesn't hold up quite like
that. More important is the support aspect, as it falls to the system
builder and not Microsoft. In the case of someone purchasing and installing
an OEM license copy, it means they are responsible for their own support.
The price difference is due in part to this fact, as Microsoft does not have
to incorporate potential support costs into it.

--
Best of Luck,

Rick Rogers, aka "Nutcase" - Microsoft MVP
[url]http://mvp.support.microsoft.com/[/url]
Windows help - [url]www.rickrogers.org[/url]
My thoughts [url]http://rick-mvp.blogspot.com[/url]

"Bill Leary" <Bill_Leary@msn.com> wrote in message
news:8912B753-CE57-4E3E-9ABC-98259A80140C@microsoft.com...[color=blue]
> "Not Me" <cargodZeroOne********.com> wrote in message
> news:3EAF3E8E-8F6D-4A5E-B81F-D3D382125922@microsoft.com...[color=green]
>> The other thing with OEM software is that it is tied to the first machine
>> it is installed on and you can not (legally) use it on another system.[/color]
>
> I keep reading this but I'm wondering just how far you have to go before
> it's "another system."
>
> I had a computer I'd built a couple of years back and installed Vista
> Ultimate OEM on it around the beginning of 2007.
>
> During the summer of '07, I replace the motherboard, video and DVD drive.
> Fired up and let Vista figure out the changes. Afterwards it said I
> needed to activate, which I'd expected. I called them up, told them what
> I'd done. They asked if I had another copy of Vista from this DVD running
> on another computer, and I said "no." They phrased the question a
> different way, and I still said "no." Next thing I know, he's giving me a
> new activation (or whatever it is) number.
>
> In the sense that it's the same powers supply, case, and hard drive, I
> suppose it's the same computer.
>
> What I wonder is, just how far could I have gone with replacing things
> before they'd have given me a hard time about it? Or if they would? The
> only thing he seemed concerned about was whether there was another
> instance of Vista FROM THAT DVD running on another computer anywhere.
>
> So, as a practical matter, how far can you go before they tell you you've
> got to get a new license?
>
> - Bill
>[/color]