I would like to pay special attention to the orientation of the top plastic ring and direction of the airflow. Take a closer look at the ring:
It is sealed on one side and has air outlets for warm air on the remaining three sides. The manufacturer specifically stresses this peculiarity in the user’s guide:
Besides, there is also a schematic of the correct airflow direction when the cooler is installed on the mainboard that can be set with this ring:
In this case the warm air should be ousted towards the case rear panel and case fan (if there is one available, of course):
Moreover, if there are ventilation holes in the case side panel, then you can direct airflow towards this panel by removing the Air Duct ring, as you can see from the illustration above. In reality, however, the air is still ousted mostly away from the cooler top. Even with the air duct ring installed, most air still goes away from the cooler top, and not sideways away from the sealed side of the ring. And this also was proven during our practical experiments, which you will get to in just a moment.