Scenarios that need OS support: Your BIOS doesn't support fan speed at all. Your BIOS doesn't doesn't support temperature-controlled fan curves, or doesn't le

Scenarios that need OS support: Your BIOS doesn't support fan speed at all. Your BIOS doesn't doesn't support temperature-controlled fan curves, or doesn't let you customise the fan curve. You want to use a different temperature sensor, or multiple, to control different fans, pumps, etc. You want to schedule different fan profiles based on time of day or some other event.