What computer works the best with HFSS 13?

Hey,

I am using HFSS 13 and my design has many small cylinders(1000-10000). Size of the cylinders is small in compare to dimension of the design . While running it I kept getting the "out of memory" message even decreasing the # did not help that much so we are going to buy a new "fast computer". Do you have a suggestion for us? What OS, processor, RAM works better for us?

Thanks,
Sun