It depends on the server, some are dual core, some are quad core, but anything less than about 2 is good.
I'm no UNIX guru either, but I have read that NFS is ok up to a certain point, beyond that it can become inefficient, at what that point NFS becomes inefficient is unknown to me, maybe someone else knows more.
I can understand your frustration, I am suffering the same frustration of late, my faith in Dreamhost ever getting things back in order is waning. I've already started looking at other providers just to get an idea of what is out there, and at this point in time I'm thinking of buying a hosting account elsewhere and moving some of my sites to the new host just for comparison purposes.
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