Help with new computer hardware

We need a new "FEA" computer in our department because our last machine was aquired for another use.  We have close to an unlimited budget but that doesn't mean we're going to spend money we don't need to.  We went with an XI computer last time and might do that again.

First, we are having trouble importing large stp files and I don't know a new machine will even help with that.  They're files from Chrysler and the larger ones aren't as likely to open, ~150MB, sometimes >4000 surfaces(?).  It seems to be consistent on whatever machine I use, see below.  The machine will process for a while, get to the last step, and then the processor just goes down to zero and SolidWorks stalls out.  This also happens when trying to put a couple large sub-assemblies together to form one large assembly.

Current hardware tried, working local:

(XP32 Core2Duo T9600 2.8GHz, 3GB RAM, Quadro FX 2700M)

(XP32 Xeon E5345 2.33GHz, 3.25GB RAM, Quadro FX 3500)

We also will use this box for running our Simulations.  We do thermal, structural, frequency, and drop.  And since the last one was faster, we did renders once in a while too.

At XI, we priced out the latest processor, i7 980X, 24GB of RAM, 64-bit, etc.  But we're not entirely sure if it's spending money we don't need to and if there are other problems with the stp files.  Any suggestions or recommendations would be appreciated!

Thanks

SolidworksAdministration