Does adding material properties to a part increase the burden on SW significantly? I went through a bunch of my models adding them (mostly so that I can find out assembly weights to work on packing systems up) and now my assemblies have really bogged down. The parts themselves don't seem effected, but my assemblies can easily have 100,000 parts in them; some over 250,000. I don't think my workstation is the problem, it's only a few months old and has an i7 860 and 16GB of memory. Has anyone seen this happen with SW2010? Any thoughts on how to fix it? Thanks in advance.