Fractal Nexus 9P Slim Fan Hub

[Tyerker]

This is my first time working with a fan hub. I'll be using an air cooler with 2 fans and 5 case fans in my Torrent case.



The manual says to connect the hub to the CPU Fan port on the motherboard, and it looks like then the actual CPU fan is supposed to daisy chain off of the hub. This seems like needless wires run around the case compared to using the CPU Fan headers right next to the socket.

Does anyone know if connecting the input of this fan hub to one of the Chassis Fan ports would cause any issues? I'm thinking the main intention is that every fan can ramp equally with the CPU fan profile, but I don't think that's what I want. I think I'd prefer to use the BIOS Fan settings to adjust to the CPU, and then the Chassis fans can still be set up to react to system temp on a different curve. I just want to make sure there's not some deeper reason why the hub connects to the CPU header, so I don't screw anything up or short something out.

 

[JLK03F150]

I have looked at similar fan hubs and always thought it was odd, and kinda stupid, to ramp all the case fans with the CPU fan. The instructions might be done that way because many older motherboards don't have any PWM chassis fan headers. My Z87 board only has one for the chassis fan & one (maybe two) for the CPU fan. If you confirm that you have a true PWM chassis fan header on your mobo, I don't see why that wouldn't work. BTW, not all 4 pin headers are PWM, that's why I suggest verifying with the mobo manual.

 

[Zerileous]

So they put that there for people using AIOs or other liquid cooling. Some motherboards will throw a fit if something is not connected to the CPU Fan header and providing an RPM. At least that's my assumption but then the diagram shows and air cooler, so what do I know.

Go ahead and connect the CPU fan to the CPU header and the case fans to the hub. So it looks like the GND FG header will interpret the PWM signal from whatever motherboard header is applied, and then apply it to the other fans while taking power from the SATA connector. It will also report the RPM from Fan 1 to the motherboard header so you'll need to make sure that one is populated. Then you will be able to set a separate fan curve for the case fans and the CPU fan. Most motherboards have some sort of temperature sensor other than the CPU itself, which you might be able to use to approximate case temp. CPU temperatures tend to be bursts of heat and if you have every fan ramp up and down with the CPU it will be super annoying.

 

[freeagent]

I have my Fractal hub plugged into Chassis fan 1 on my board, that would be the rear fan as it ramps the quickest. These Fractal fans are slow movers so it is helpful. I also had to plug a fan into 1 and 4 on the Fractal hub to get them to spin and light up. I thought that was weird, but I didn't read the instructions so..

 

[EarthDog]

Some motherboard headers have the ability to change what metric/source it uses to ramp up. Be it chassis temp or gpu temp, motherboard temp, or others.

 

[JLK03F150]

I looked up the mobo manual. It seems you need to set one of the three chassis fan headers to either DC or PWM & plug the new fan hub there. Agreed, the CPU cooler fans should go to the CPU header.

 

[Tyerker]

Thanks guys. I ended up routing the 2 CPU fans to the CPU_FAN and CPU_FAN_OPT ports, so they appear to sync based on CPU temperature.

Then all of my CHA_FAN headers are PWM supported, so I used one of those, and all the fans are spinning. I set the CPU fan profile to turbo, and the Chassis fan to Silent, in the BIOS. Everything appears to be working as intended.

Appreciate the insight. I was a little paranoid because of a Gamers Nexus video about these hubs failing, but it seems like that was a very short-lived issue.