I have a 5820k. When I first bought at X99 launch, I was testing my OC on air with a Noctua NH-U14S. At 4.4Ghz, temps were in high 80C, peaking in 91C range in Realbench. Gaming temps and idle were much lower though. Case was 800D with plenty of airflow. Really depends on your goals, system usage, case airflow, ect. to help with decision. If your not pushing for a higher OC and voltage within reason, your cooler should be fine.