Yeah, the sig is right--except its Mac Pro 5,1 and I forgot to mention I have 2 processors. I just recently did the El Capitan upgrade, but Logic X drag was slow before that. Everything else in Logic (and elsewhere) has been working fine post-upgrade. Most of the instruments are hosted on a couple slave pcs in VEP or on the main rig in VEP. I don't use to many extra plugins in Logic either. Anyway, I can open a brand new empty session, put 20 tracks in it, and I still get the same slow drag speed...