My Mac Pro 5,1 has been having an issue where its not properly cooling my system it blows but its not maintaining temperature correctly. The CPU can get up to 70 degrees and will eventually crash. The fans don't ramp up to cool it off properly. I have mac fan control set to automatic and the fans are working correctly because they all go up to full rpm when i set it to full blast. I recently put some high-end thermal paste on them to try to remedy the situation and made sure the thermal paste was properly set over the cpu. Still just as much of a problem though. I'm using a dual socket system with the upgraded 3.46ghz cpu's. Recently also encountered an issue where it fried my 1080TI because its fans were not cooling properly as well. My current solution is setting mac fan control to full blast and when booting setting an auxilary fan over the cpu area. 🙄