I can't believe it but after 4 years of running this same wonderful, stable rig, without any recent changes to kexts or OS version 10.11.5, I am getting regular and seemingly random freezes of my rig. I can be running no applications or Safari and total lockup occurs. I see no spikes in CPU or memory usage. Just total screen freeze and I have to power down. I've run basic memory and SSD checks and all looks good there. The freeze can happen 5 minutes or 5 hours after I've logged in....
Suddenly getting system freezes in El Capitan
Suddenly getting system freezes in El Capitan