Detecting When Computer is Working

[kiltman67]

How do devices, like Fan Controllers for example, detect that a computer is "working"?

I know the HDD Busy LED is connected to the Motherboard but in reading the manuals for these devices (one of which being the Aerocool GateWatch) it makes no mention of connecting the device to the same connector on the motherboard, so how do these devices know when all they seem to have externally are connections for fans and temperature sensors.

 

[kiltman67]

Surely you got to connect a molex to it for power? When you press the power switch, psu kicks in and starts supplying the controller.

I may have misunderstood the description but the AeroCool Gatewatch seems able to report when the computer is busy in the same way as the HDD Busy LED on the case.