Perhaps I'm just intolerant to the things being hot. I got a decent uncomfortable burn from it. About the same as a passive heatsink on a CPU that gave me an overheating alarm. The one in my supermicro chassis doesn't get too hot with the airflow in there. So I just put a 40mm fan on it and it stays cool to the touch. This setup is not in a case at all, zero airflow. I mess with it pretty often and it runs nearly 24/7. So I don't like it hot, makes it uncomfortable to work on. Maybe I'm just weird, I'm ok with that.