Question Quick question: where do I connect the AIO pump cable?

Aug 31, 2020
I know that usually you are supposed to connect the AIO fans to cpu_fan/cpu_opt and then the pump to aio_pump if the mobo has it but the problem here is that the fractal s24 has a built-in fan header so you directly connect the two fans to the radiator and so there is only one cable that powers all the parts, so, where does this cable go? aio_pump or cpu_fan?


Actually, it should plug into the CPU_FAN header for three reasons. One is that this header is guided in its automatic control by a temperature sensor inside the C{PU chip, whereas the SYS_FAN or CHA_FAN header is guided by a different sensor on the mobo. Secondly, the second major function of any headere is to watch the speed signal of the connected device for no signal, which would indicate FAILURE and potential danger of expensive overheating and damage to your equipment. The CPU_FAN header is especially attentive to this function, so it is important that the speed it watches IS the main cooling device for the CPU chip. If you plug the pump in elsewhere, the CPU_FAN header cannot monitor it for failure. I am not completely sure that the PUMP header will do the same careful monitoring.

Lastly, unlike most AIO systems, this one DOES use variable pump motor speed. There is a setting you adjust on top of the pump. Normally, set it to AUTO. In that setting, the CPU_FAN header will govern the speed of the rad fans, and the motor itself will use its own sensor for the temperature of the circulating liquid and adjust its own speed. The alternative PWM setting apparently has the pump motor follow the fan speed settings. So there is NO need to ensure the pump is connected to a constant 12 VDC, because that is what it WILL get from the wires from the 4-pin CPU_FAN header that is set to PWM Mode.