Hi,
As you are running VM, I am assuming this is for your development purposes. Minimum specs required is as per the teched article below:
https://technet.microsoft.com/en-us/library/hh699840.aspx
You need at least 2 GB RAM but for decent performance, go for recommended settings. Also for development perspective, we generally install all on one machine to make sure it is easy to share between developers and there is no network latency
that we need to rely on.
Hope this helps.
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Minal Dahiya
blog : http://minaldahiya.blogspot.com.au/
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