I have 3.9mhz I7 - 64 bit W7 - 32 gb 2400 ram - on an assembly it takes solidworks about 20 minutes to set a mate of a washer on a hole - and 2 of these are needed -

Solidworks only pushes the CPU to only 8 or 9% - when a test program pushed all 12 cores to 100%. I am considering trying a 1 tb ssd but I have OS on C:  - Solidworks and E: and drawing files on F:  - so adding SSD to which would improve 'performance' - if you can call it that since it is so pathetic I won't be able to finish my assembly this century -

The lack of Solidworks' ability to push the CPU seems to be more of the problem than disk access but I'm willing to try almost anything - since the customer insists on Solidworks - which I thought was only 5 or 6 times slower than a real CAD program but now turns out to be about a thousand times slower.