CPU Over Temperature Error after replacing water cooling radiator fans

[YonathanZ]

Hi,

 

My PC has a Corsair water cooler for the CPU. The original fans were loud, so I replaced them with Noctua NF-P14s redux 900 fans. 

The original fans have 4 pins (PWM for RPM control) while the Noctua ones only have 3 pins.

When I turn my PC on, all the fans work though I get an error which says: 'CPU Over Temperature Error'.

 

I don't see how the CPU can overheat instantly, even if the fans were not working at all, so I assume it might have to do with the fact that it cannot communicate with the CPU fans.

Either way, I'd appreciate your help with this.

 

Thanks.

[Levent]

Have you connected the pump? If you dont connect your pump or its not working it will throttle almost instantly.

[YonathanZ]

Well, I only disconnected the older 2 fans and connected the new ones. Everything else was untouched.

[Jeppes]

Is the pump connected to cpu header? Could be an error message just because of no fans connected there.

 

Also a bit weird move to buy 900rpm for rad. You can run 1500rpm fans slower too.

[YonathanZ]

The USB cable that can be seen in the above photo is connected at the other end to a header on the motherboard called USB 1112, as can be seen here:

 

As for the 900 rpm choice, that's due to a misleading listing on Amazon. They're listed the 900 rpm version as 'PWM' and the 1400 RPM version as 'no-PWM', while in reality none of them have PWM.