Why is my slower CPU outperforming my faster CPU in mesh speed?

I'm running the same version of SW (2016) on a computer with an i7-8700K (3.7GHz, 6 cores) and an i6-4690 (3.5GHz, 4 cores). The i5 can mesh my study in about 9 minutes. The i7 takes 12 minutes. Same model, same mesh settings. Both PCs are running off an SSD. Is there some magic setting I'm missing here? The mesh in question is mostly shell elements with several solid parts, 14k total elements, high quality, no automatic transitions. Color me confused. My client put some serious dough into a quality workstation for this project that should be at least 20% faster, but it's actually 20% slower???

SolidworksSimulation