Tricking a fan header to activate (no RPM reading)

[jack_l2]

Hi all,

I have a D5 Liang strong pump which I connected the 12V and the Ground wires directly to the PSU itself. That left me with a RPM sensor wire (1 pin) which I connected to the FAN / Pump headers.

My motherboard (MSI x299 Gaming M7 ACK) does not seem to read the RPM signal if a 1-pin header is connected to the FAN header. I think its expecting a 12V and a Ground before "enabling" the fan header itself and afterwards being able to read the RPM signal.

What are the different ways I can "trick" the mobo to read that RPM?

One way is to connect another FAN on the 12v/GRND, and attach the pump's RPM wire for the third pin of the fan. It would power the fan, but read the RPM of the waterpump.

Any other ways to do that?

[wattermain]

Hey jack_12 After reading your post I was curious to see how my setup works. I am running an Asus P8Z77-I. I have an RPM/PWM cable from a Phobya fan splitter connected to the CHASSIS FAN header ( upper) and an RPM cable from the pump connected to the CPU FAN header.(lower). The RPM cable is actually coming from the RPM connector of an Aquaero but it worked the same way when it was coming from the pump itself.





The bios only reads the RPM of the pump on the CPU FAN header.





If I remove both cables or if I put the RPM/PWM cable from the Phobya splitter on the CPU FAN header I get....




If I put the RPM cable from the pump on the CHASSIS FAN header I get the same error message.





Not quite sure why there's an error message when the Phobya splitter is connected to the CPU FAN header.

[wattermain]

After rooting around for a while, I found that the last fan that is connected to the Phobya splitter had been disconnected, so I wasn't getting anything in the bios. All better now. So I guess the bottom line is that this board will start with just an RPM signal at the CPU FAN header. Thanks for helping me fix my problem