How to license sql2012 VM

Our plan to buy 2 physical server where each servers comes with 2 physical CPU @ 8 core each with hyperthreading. we also plan to install with windows 2012 Hyper-V.

So in sql2012 license scheme, If I run sq2012 on VM with 4 virtual core, is that means we only need to buy 4 virtual core license instead of buying 8 core license s per CPU core ? If we decided to add VM with 8 core CPU and enable sql2012 with 8 core CPU, what will be the impact if we don't buy the additional license ?
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x-menIT super heroCommented:
you only have to by the number the number o licenses equal to the number of cores viseble (or usable) to the SQL Server.

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Sikhumbuzo NtsadaIT AdministrationCommented:
I got this PDF from a Microsoft Partner - hope it will help you.

...see attached file.
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Microsoft Virtual Server

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