I completely agree with Kjanx. As you probably know OEM licences are tied to one machine and any major upgrades (a mother board is considered major although your allowed to change the CPU once without any problems) will negate the licence and a new one will need to be sought from Microsoft. As Kjanx rightly says though, all you need to do is ring the Tech' at Microsoft and explain the situation. As long as the copy of Vista isn't on more than one machine they couldn't care less!

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