It's far from obvious because the amount of heat generated inside of a laptop is going to require constant airflow. The idle temperature of a CPU is 86 to 104 w

It's far from obvious because the amount of heat generated inside of a laptop is going to require constant airflow. The idle temperature of a CPU is 86 to 104 which is always going to be warm and browsers use significant amount of resources and even more so when they're playing video. There is never a time when your fans should be off, ever. Even liquid cooled CPUs require airflow to dissipate heat.