[SOLVED] Where do I connect my AIO pump?

Nadsj

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Jun 19, 2020
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I have the psi b450 tomahawk and the Lian Li Galahad 360 AIO. Do I connect the pump to the cpu fan header? Or do I connect it to the pump_header? Also the radiator fans are daisy chained and connected to the sys_fan header is that correct?
 
Solution
Fans generally have a MTBF (Mean Time Before Failure or service life) of 50,000-150,000 hrs use.

Pumps generally have a MTBF of @ 50,000 hrs.

Pumps are expected (by the manufacturers/OEMs) to fail first.

Cpus have their own protective systems, used through the motherboard, one of which is the cpu_fan header. If this header detects a low/no rpm signal, the cpu can/will shutdown/refuse to boot to protect itself from possible thermal damage.

Because of this, manufacturers will stipulate the pump goes to the cpu_fan header and the fans/splitter to any other sys_fan header.

Which is next to useless. There will be no control of the pump by the cpu_fan header (pumps are almost always 3 pin DC, the cpu_fan header is only PWM) and the fans...
I have the psi b450 tomahawk and the Lian Li Galahad 360 AIO. Do I connect the pump to the cpu fan header? Or do I connect it to the pump_header? Also the radiator fans are daisy chained and connected to the sys_fan header is that correct?
When an AIO cooler has separate power leads for pump and fan(s), rule of the thumb is to connect pump lead to pump_header or AIO_pump header while radiator fans should go to CPU_Fan header. Idea is to have radiator fans speed be regulated by CPU temperature, SYS_Fans are regulated by some other part's temps.
There's also this:
View: https://www.youtube.com/watch?v=qDPVRXk5BM0
 
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Karadjgne

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Fans generally have a MTBF (Mean Time Before Failure or service life) of 50,000-150,000 hrs use.

Pumps generally have a MTBF of @ 50,000 hrs.

Pumps are expected (by the manufacturers/OEMs) to fail first.

Cpus have their own protective systems, used through the motherboard, one of which is the cpu_fan header. If this header detects a low/no rpm signal, the cpu can/will shutdown/refuse to boot to protect itself from possible thermal damage.

Because of this, manufacturers will stipulate the pump goes to the cpu_fan header and the fans/splitter to any other sys_fan header.

Which is next to useless. There will be no control of the pump by the cpu_fan header (pumps are almost always 3 pin DC, the cpu_fan header is only PWM) and the fans will then respond to case temps which never get above the 50's.

So almost everyone uses the fans on the cpu_fan header and puts the pump on the sys_fan header. Motherboard manufacturers clued into this and started putting aio_pump headers on motherboards which are generally not controlled but are full 12v and tach, so perfect for the use.

That way the pump is always powered and the fans then respond to cpu temps, ramping up/down as needed for the loads.
 
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Solution

Paperdoc

Polypheme
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Karadjgne is correct above, but I'll add a small note. The info about special protection against cooling failure by the CPU_FAN header is right, and that is an important second function of that header. It is especially important for the PUMP unit in an AIO system because that is the most critiical part from a failure perspective. This is NOT normally done nearly as well by a SYS_FAN header. BUT almost all mobos that DO have an AIO_PUMP header also DO that important failure monitoring on that header. So that is the ideal place to plug in your pump.
 
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