Confused on Best Processor for Solidworks

I am trying to price out a new workstation for one of our CAD users and after going through some of the posts here and other information on the web, I have to say that I'm a bit confused as to what the best processor is.  I know that this is some subjective based on what we do with it.  So, we do some assemblies, nothing I would call huge.  The majority of what we do is tooling design so we use surfacing, indenting, combining, splitting  a lot.  I know indent and splitting seem to take a lot of resources but will these features use more than one processor on the computer?  Or are we still better with a single, 6 core processor that is as fast as we can afford?  I here the i7 name tossed around but looking at Dell's site (locked into a Dell at this point) I don't see them offered on any of the Precision Workstations.  How would a W3680 compare to that?  Is that the best single processor?  What would be a good dual processor, E5620?

So I guess here are my questions.

-1 processor system or 2 processor system?

-Whats the best processor for a 1 processor system?

-Whats the best processor for a 2 processor system?

-Based on what we use Solidworks for, is there a benefit for a 2 processor system?

Thanks for any input you can provide!!

SolidworksAdministration