How to control 6+ fans?

[unraidun]

Just ordered a 15 bay server chasis...

 

https://www.amazon.com/gp/product/B0091IZ1ZG/ref=ppx_yo_dt_b_asin_title_o01_s00?ie=UTF8&psc=1

 

...and I'm trying to figure out how to wire up these fans. They make 4 pin PWM 'hubs' that would allow me to control them all...

 

https://www.amazon.com/SilverStone-Technology-Silverstone-Splitter-SST-CPF04-USA/dp/B07N3HP8S5/ref=sr_1_1?keywords=SilverStone-Technology-Silverstone-Splitter-SST-CPF04-USA&qid=1578452223&sr=8-1

 

...however the reviews say it ONLY works if you plug into the CPU fan header. Which would be great if I wanted to ramp up the case airflow when the CPU got hot, but I'm more concerned about ramping up when the DISKS get hot. Apparently if you plug this hub into the cha/sys fan header, they will just run 100% at all times.

 

So how are you guys dynamically controlling large numbers of fans for your machines?

 

Thanks!

 

 

[TobiRh]

About the fans in the case:

From the pictures of the case the included fans all use Molex Splitters. That means they can not be controlled and always run full speed.

 

Of cause the fan can still be "voltage controlled". Maybe you can move the Pins in the Molex around so he would only run with 7 Volts. (Do NOT use them for something else then!!) Still not controlled, but noise vs. cooling may be acceptable.

I am not sure if the motherboard Fan headers in 3-Pin-Mode absolutely require a tacho/speed signal to work. (I believe not.)

If not, you might be able to change the wiring to attach the fans there. (Crimping or soldering required.) If a tacho-signal is needed, you would need to have one Fan that provides that tacho signal.

This is basically what Splitter is for (partly). 

Personally I would be afraid to overload the board when paralleling up 5 fans. And this is the other part of that splitter: It takes power from a SATA power cable and distributes the PWM signal to all the other (PWM!) fans.

 

I would advise you to get new 3- or 4-pin fans - depending how you want to control them.

How to control them depend mainly on your motherboard. (I do not know what external solutions may exist and how well they work with Unraid.)

 

About the splitter:

That thing is intended only for 4 Pin Fans. One Fans speed signal is send back to the MoBo. The PWM from the Mobo signal is send to all the fans.

If it works depends on your board. The board, or more specifically the fan header you use, must run in 4-pin-PWM-mode. It seems some boards feature PWM on the CPU fan header and the case headers are only voltage-controlled.

You need to carefully read your motherboards manual.

 

About controlling fans:

Depends on the board you use. For example for AsRock/SuperMicro there is a special plugin to control the fans via IPMI. Non-server boards will be easier to control. As long as there is a way to control the fans via software there is likely a solution around here. Maybe post you intended motherboard and somebody can advise.

[unraidun]

Thanks for the info, just ordered and ASUS AM4 TUF Gaming X570-Plus MB...

 

https://www.amazon.com/ASUS-TUF-X570-Plus-Motherboard-Lighting/dp/B07SXFK1TP/ref=cm_cr_arp_d_product_top?ie=UTF8

 

Which has SIX 4pin pwm headers! So instead of trying to convert the molex fans, I think I will just scrap them and go with these 4pin fans...

 

https://www.amazon.com/gp/product/B07HC782D5/ref=ox_sc_act_title_5?smid=ATVPDKIKX0DER&psc=1

 

and I heard its safe to run two fans off one header as long as they dont exceed 1amp, so I got some splitters too.

 

Now I should have all the control/monitoring I need right from bios/unraid right? No need for a hub/fan controller?

 

Although that begs the question, I want these fans to spin up when the DRIVES get hot, not so much the case/whatever the fan headers are sensing. Can unraid do that?

Edited January 11, 2020 by unraidun

[TobiRh]

According to the manual p.28 you can draw 1 A on each header. Your fans are 0,08 A each. So you are fine power wise - and the built-in splitter with these fans is nice.

(Side Note: The Case has 6 x 120 mm and 2 x 80 mm fans. You specifically only mentioned the 120 fans. Just saying. Also - fan extention cables for the front fans needed, maybe?)

 

When looking at Q-Fan Control in the manual p. 55 it looks like the two CPU Fan headers share one PWM signal and the others can be controlled separately.

I pretty sure there is a ASUS software to control the fans from windows, so BIOS fan control can be overwritten.

-> As far as having the hardware for software controlling the fans this looks very promising.

 

As to controlling them by HDD temperature this is a rabbit hole in itself. Unfortunately so far nobody has jumped in here with the same hardware and shared his story how easy and straight forward it was or something... But also no nightmare stories either. 😁

 

Take a look at dynamix_auto_fan_control plugin.

Without searching too much in it I noted other X570-Chipset users in the tread wrestling with fan control right now:

(Generally this is mostly about the PlugIn detecting the sensors on your specific board.)

  

Maybe consider searching for 'fan speed' and you MoBo name - with some luck you find others have gotten it working or or at least posted a similar build so you could ask them. 

(Or really nobody ever posting, which means it works out of the box - maybe, hopefully...?)

 

Otherwise I am afraid you have to jump in I guess and give it a try.

(If you have one or two spare PWM fans you could postpone ordering the new ones until you got fan control working with them.)