Could be the case. Doesn't seem to have much airflow. My 3090 is idling at 45 and the hottest I've managed to get it under heavy load is 77, and I had been pushing it for hours by that point. Might be worth experimenting with removing panels to see if that helps. Maybe a custom fan curve as well, but I wouldn't expect the GPU fans to really be spinning at idle unless there was a case/airflow problem.