How to run radiator fans at low RPM?

[BenTan]

Hi,

 

I'm currently planning my first water cooled build and am trying to figure out a way to run 6-8 fans at low RPM (around 500 RPM)

 

I'll be using Corsair SP120 and AF140 quiet edition fans. I currently own 3 of them and they are non-PWM. I'm not too concerned with PWM fan control. I just want to run them at around 500 RPM each.

 

In my current build, I'm using corsair's voltage step down adapters but they're not effective enough. 2 voltage step down adapters get an AF140 quiet edition to about 880 RPM.  Motherboard fan control isn't an option for me as the fan control on my motherboard is just plain terrible (Only the system fan 1 header seems to be able to control fan speed).

 

I'm looking for a fan distributor or splitter that will run fans at extremely low RPMs. I've been looking at the NZXT Grid and some ModMyToys fan distributors.

 

Any help is appreciated,

Thanks

[Bleeding Moot]

just go into ya bios to change ya fan curves, thats what ive done.

[Deli]

Fan hub doesn't reduce or control fan speed. Get a fan controller and a fan hub if you want to individually control more than 4 or 5 fans to the exact speed you prefer.. 

 

http://www.newegg.com/Product/Product.aspx?Item=N82E16811990008&cm_re=fan_controller-_-11-990-008-_-Product

[BenTan]

just go into ya bios to change ya fan curves, thats what ive done.

Changing the settings in the bios only affects the fan connected to the system 1 fan header. It's probably because only the CPU and System Fan 1 headers of my motherboard support 3 pin fans. The rest of the headers only support 4 pin fans and the ones I have are 3 pin.

[BenTan]

Fan hub doesn't reduce or control fan speed. Get a fan controller and a fan hub if you want to individually control more than 4 or 5 fans to the exact speed you prefer.. 

 

http://www.newegg.com/Product/Product.aspx?Item=N82E16811990008&cm_re=fan_controller-_-11-990-008-_-Product

Are there any other alternatives? I don't want to use any of the drive bays for aesthetic purposes. It doesn't have to be at exactly the RPM I want.

 

What about this?: http://www.performance-pcs.com/modmytoys-4-pin-pwm-low-profile-power-distribution-pcb-8-way-block.html

[soup]

Resistors in series with the fans?  Same idea as Noctua's LNAs.(and ULNAs)

http://www.amazon.com/Noctua-NA-SRC10-Accessory-Low-Noise-Adaptors/dp/B00KG3KELQ

 

They basically reduce the noise by reducing the voltage dropped across the fan motor so the speed is reduced.

[BenTan]

Resistors in series with the fans?  Same idea as Noctua's LNAs.(and ULNAs)

http://www.amazon.com/Noctua-NA-SRC10-Accessory-Low-Noise-Adaptors/dp/B00KG3KELQ

 

They basically reduce the noise by reducing the voltage dropped across the fan motor so the speed is reduced.

How much would noctua's low noise adapters lower the speed in terms of percentage? What about their Y-splitters?

 

I'm looking for something that I can place behind the motherboard tray and connect all my fans to and control them using PWM.

[soup]

How much would noctua's low noise adapters lower the speed in terms of percentage? What about their Y-splitters?

 

 

I do not know in percentage terms (different for different makes ?) but the LNA is equivalent to supplying the fan with 9 volts instead of twelve, whilst the ULNA is equivalent to supplying the fan with 7 volts.

AFAIK the Y splitters do not have resistors in them they merely "split" the power supplied to one header into two .  They will be engineered to have minimal impact on the speed/voltage supplied to the fans.