H45 MB connections?

[Mang]

Hello.

I bought the H45 water cooler but can't make it work properly. I'm pretty sure I installed it correctly (thermal paste, screws). The computer turns on, the temperature rises up to 100ºC, and after some time it shuts down. At first I thought the pump might not be working, but I tested the tubes and one of them gets really hot and the other is cool, so... I guess it is working?

I have a Biostar X470GTA motherboard that has two 4 pin cpu_fan and two 4 pin sys_fan. I tried connecting the pump power plug (3 pin) in both cpu and sys fan connectors.

I don't know where exactly to put them. Does the 3 pin connector from the pump work on a 4 pin?

 

[Mang]

Anyone?

[c-attack]

On 5/9/2022 at 9:22 PM, Mang said:

but I tested the tubes and one of them gets really hot and the other is cool, so... I guess it is working?

Unfortunately this is a bad sign, not an indicator of proper functionality. The coolant only drops about 1C after a pass through the radiator so the tubes should be indistinguishable for temperature on touch. That is heat building up from the cpu block and slowly rising up the cpu outlet tube. The continually climbing temp to shutdown is another classic zero flow indicator. 
 

The 3 pin connector should work on the 4 pin PWM cpu or sys fan. If they are PWM only it’s not a problem as this maintains the full 12v signal the pump needs. However, if the mb header automatically switches between DC and PWM, you need to lock the pump header to 100% in the bios fan controls. This can be done on most boards by setting the fan header to “disabled”, “full speed”, all dots to 100% or any other language indicating 100% at all times. The fan you can set to change speed, but the pump needs to be running at its maximum at all times.