Connect 10 fans to the motherboard ? Please Advise

Prochaos

Prochaos

Prochaos

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Simple question am i about to purchase https://www.overclockers.co.uk/phanteks-pwm-fan-hub-ca-009-pt.html
and connect my 10 fans to to it, power it from the psu and connect it to 1 motherboard fan header so i can controll the speed of the fans.

ive been running all 10 fans from a lamptron fc5v3 for over a year and im getting fed up with it, cant bring the fans below 1000rpm or they will drop down to 0rpm constantly having to reset the fans rpm to 1200 when i turn my pc on because some of them are down to 0 rpm, 1200 rpm is just noisy, i want them all at 800 rpm.

i just want a solution to power them off the psu and connect them to motherboard so i can set their rpm from there, im just getting fed up of this fan controller and im at my wits end, please assist me in this solution.

For anyone's interest im aware 10 fans is a lot but im very happy with this configuration and its has been working very efficiently all this time after configuring the best and optimal configuration in pull vs pull vs position of said fan, here is a simply diagram that has been my final setup for the past year after experimenting.

fan_and_temprature_sensors_placements_for_fan_co.jpg


Here is how it currently looks, only difference is the cables

20150210_171412.jpg
 
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Are you sure 800rpm is within all fans operating range?
The black/brown ones looks like Noctua IndustrialPPC ones, and they should be fine (atleast the 120mm ones), but maybe the others do not spin with that low voltage?

Anyways, the phanteks fan hub is effectively the same thing as connecting all fans to only one channel on your current controller, meaning you can only use one of the fans to measure speed, and while all the noctua 120mm fans should spin at roughly the same speed for a given voltage, the others might not.
 
Sorry i forgot to mention they are

7 x Noctua NF-F12 IndustrialPPC 2000RPM IP67 PWM 120mm
3 x Noctua NF-F12 IndustrialPPC 2000RPM IP67 PWM 140mm
 
Well that might be your problem right there. a lot of fans minimum rpm is often 50% of its max so the 1000 rpm cutoff makes sense. Might want to check what the exact range of your fans are before considering any thing else
 
Oh, they're PWM fans, d'oh!

Both your current controller and the phanteks fan hub control the fans via voltage (3-pin). And while the phanteks hub have pwm as input, it converts the pwm signal to voltage control.
It might be that your fans do not go as low as they can (5-700 rpm range according to noctua themselves), because you are controlling them via voltage, and not PWM.

You should start by trying to control them via PWM and see how low they can go. Unfortunately, as far as pwm go, there aren't a whole lot of controllers that support pwm directly, the vast majority is voltage control only.
The one I can think of off the top of my head is aquacomputer aqauero 6, which come with a really hefty price.

What you could do is get a pwm splitter cable with a molex/sata power input, like this:
https://www.overclockers.co.uk/akasa-flexa-fp5s-5-fan-pwm-controller-ak-cbfa07-45-cb-079-ak.html
The molex provide all the power you need and you use the CPU_FAN or CPU_OPT headers on your motherboard to control the speed.
note: this was the first i found, there are more types with different amount of fan connectors, maybe even one with ten of them.

Edit: One drawback with this type of cable is that you can not completely stop the fans (apart from turning off your computer :p ), if the pwm signal is missing/zero, they will run at full speed
 
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sneakysnail said:
Well that might be your problem right there. a lot of fans minimum rpm is often 50% of its max so the 1000 rpm cutoff makes sense. Might want to check what the exact range of your fans are before considering any thing else
Click to expand...

I have the 3000rpm 140mm fan and it's minimum is 800rpm. The 2000 version can go down to 500.
 
Thank you for the advise so i will purchase

1 x https://www.overclockers.co.uk/akas...-5-pwm-case-fans.-ak-cbfa03-45-cb-070-ak.html Seems to have better braided cables and is molex instead.

and use my current 4 x noctua 4 pin Y cables to on the akasa cable and plug the remainng 1 into another mobo fan header to make up all 10 fans and connect it to the CPU fan header, i noticed on the following review on another website of the https://www.overclockers.co.uk/akasa-flexa-fp5s-5-fan-pwm-controller-ak-cbfa07-45-cb-079-ak.html that a buyer they had the following to say, so i will daisy chain the fans to the akasa cable.

"I like the SATA power connector, helps reduce the cables coming from my power supply because I just use the extra SATA connector at the end of the power line supplying my hard drives. Having the cables separate could be a problem for some but it does provide more flexibility to connect fan cables that aren't able to reach a central point. Unfortunately the PWM signal doesn't work with anything other than the CPU PWM connector. Fan connectors 1 and 2 manage to control my fans without a problem when the fans are plugged in directly but aren't able to transmit the PWM signal when connected through the splitter. It is strange to have the PWM signal work perfectly through the splitter when connected to the CPU header but not to the other fan headers.
If you only have 5 PWM fans in your case you won't have a problem but when you have more than that you'll need to daisy chain these splitters."

And a similar review for https://www.overclockers.co.uk/akas...-5-pwm-case-fans.-ak-cbfa03-45-cb-070-ak.html

"Allowed me to control all 9 fans via pwm, only issue I had was it would not work with my Case pwm header (ran fans at full speed and no pwm) only my Cpu Pwm fan header so had to daisy chain two of these together and run all 9 fans off the cpu header. This worked perfectly! "
If you have any other recommendations then please, im all ears.
I really do appreciate your time and advice :)
 
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On 99% of all motherboards out there, the only headers that are PWM are those named CPU_FAN and CPU_OPT (those located close to the CPU socket).
The other 4-pin connectors (usually named something like cha_fan) output a constant +5V on the PWM header pin, causing PWM fans connected to run at full speed.
 
Yeah, that should work fine. There might be other hubs with more connectors. I myself use a Phobya 8-fan splitter, which also have a molex power connector.

I would link it, but ocuk dont stock it, competitor sites are not allowed and phobyas own site is a flash abomination where you can not link to individual pages.

Here is a youtube unboxing vid (i hope thats allowed):
https://www.youtube.com/watch?v=McF1VhdeAD8
 
Just wanted to say thanks for the advice, after a lot of tweaking and trouble shooting ive managed to get them to stay at 750 - 800 rpm, keeping the noise down and it hasnt affected the temperatures much.

The bios fan controls were competing with asus suite 3 - fan xpert 3 for some silly reason, so in the end i changed (Asusfancontrolservice) in services to manual which keeps it off unless i want it on so the bios is able to control the fans by its self now.
 
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