Upgrading Win7 to Win8 usinf full version?

[GoogalyMoogaly]

I'm tempted to move to Windows 8.1 (and then 9) from Win7.
However what I'd like to do is rather than doing a full clean install, I'd like to upgrade my Win7 to Win8 (probably do a fresh install for Win9).
The reason I'd want to do it with a full version rather than an upgrade is that I'd like to use the old Win7 (and key) on another PC.

Is this possible?

 

[teenwolf]

keep 7

 

[demonix]

If the windows 7 install was on that computer when you got it, then it can't be installed on another PC as it's linked to the motherboard.