12 case fans. Fan control problems!

Mark_D

Mark_D

Mark_D

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I am in the middle of a new build and have finally got to the stage of turning it on and installing the OS. I'm using a Lian-Li DK-Q2 case which has a total of 12 case fans and therein lies my problem.

My motherboard is a Gigabyte Z170X Gaming 7 which has three system fan headers. "No problem!" I thought and I bought three Akasa FLEXA FP5S PWM cables which split one sys fan header out into five separate plugs and are powered by a SATA connection from the PSU. The problem is they don't seem to want to work! The fans come on and stay on at 100% regardless of any settings I change in the BIOS. I have also downloaded Speedfan which doesn't seem to detect any fans at all. I also tried Gigabyte's own Windows app and setting the fans to the "Silent" preset had no effect. I'm now looking at some kind of different solution. Can you guys recommend me a fan controller which will be capable of running 12 fans in this config:


4x Corsair ML120 Pros grouped as rear intake fans (Power draw of 0.3A each)

8x Akasa AK-FN058 Apache Blacks grouped into 4 on the left and 4 on the right side of the case pushing air out through two 480mm rads (Power draw of 0.33A each)


Another issue is that my case has no 5.25 drive bays which I could slot a controller head unit into so it would have to be some other solution, but I have no experience whatsoever with fan controllers so I could use a little insight from you guys! :)
 
Maybe your fan header doesn't support PWM control. Check your manual.

Does a single fan work when connected?
 
I've yet to test a single fan because the design of the case and the fact that I have a customer water cooling loop installed makes it an utter pain to get to the cable management area. That's on the list of things to do this evening, but the boards fan headers are definitely 4-pin PWM capable.
 
I'm thinking that the header would try and alter the speed by lowering the voltage, which then fails because you're supplying permanent full power through the SATA cable.

Certainly there are fan controllers that will do the job, including ones where you just set the fan curve profile and leave it to happily PWM itself. Most require a bay mount or two, but if you just set them up to do their thing then you could mount it inside the case somewhere hidden away... or even to the outside if you don't mind a bit of modding... or externally, perhaps underneath at the back?
 
ttaskmaster said:
I'm thinking that the header would try and alter the speed by lowering the voltage, which then fails because you're supplying permanent full power through the SATA cable.

Certainly there are fan controllers that will do the job, including ones where you just set the fan curve profile and leave it to happily PWM itself. Most require a bay mount or two, but if you just set them up to do their thing then you could mount it inside the case somewhere hidden away... or even to the outside if you don't mind a bit of modding... or externally, perhaps underneath at the back?
Click to expand...

I'm thinking you might be right! That makes perfect sense and I hadn't thought about it that way. If you have any experience with them can you recommend me a controller which would do the business? There's plenty of room to mount it inside or underneath the case. I'm not averse to a bit of modding either!
 
Yup, i had the same problem with my z97 gaming 7, i tried using a phanteks fan hub with a sata connection and it just went on full power all the time, the only header it actually worked on was the CPU header.

Only the CPU header had the speed control wire on pin 4, the other headers have it on pin 2, the others had voltage control on pin 4. I just run a few splitters from my headers and use a few splitters on the hub and im using nearly double the amount of fans as yourself, personally splitting up the controls works better for me as i have fans coming on at different temps, i dont want 20+ fans all just coming on together. Maybe the wire can just be moved to pin 2 but i wouldnt want to say as i dont know how fan wires work.
 
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Mark_D said:
I've yet to test a single fan because the design of the case and the fact that I have a customer water cooling loop installed makes it an utter pain to get to the cable management area. That's on the list of things to do this evening, but the boards fan headers are definitely 4-pin PWM capable.
Click to expand...

Only the CPU fan connector is PWM capable. Just because the headers have 4 pins means little when Gigabyte make boards.

Edit: Hmm already noted above.

Shame you bought PWM fans really as they don't work brilliantly on DC controllers.

Can you split the PWM off your CPU header and use that, or perhaps your gpu PWM?
 
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Mark_D said:
I'm thinking you might be right! That makes perfect sense and I hadn't thought about it that way. If you have any experience with them can you recommend me a controller which would do the business? There's plenty of room to mount it inside or underneath the case. I'm not averse to a bit of modding either!
Click to expand...

I prefer manual controllers myself. PWM isn't really my thing.
A quick wander through the shop should yield some results, both spec-wise and aesthetically. Just pay attention to the fan wattage and how many watts each channel can handle.
I see you have a slim drive slot, so you could mod that...

Alternatively, cut your own bay easily enough...
You'd need to cut a wide I-shape, as in two horizontal cuts the same width as the fan controller, split by a vertical cut, so it looks like this:

---------------------------- ----------------------------
I
I
---------------------------- ----------------------------

OK, those 'I's should be in the middle. Can't seem to make the flippin' thing work.

Then fold the two sides inward, drill holes for the mounting screws and there ya go. File the sharp edges off and possibly paint over the cut edges or something.
 
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i was the same way until i discovered speedfan last year ttaskmaster, that program is great, ya can set up all your fan groups separately all in the same program.
 
BluD said:
Yup, i had the same problem with my z97 gaming 7, i tried using a phanteks fan hub with a sata connection and it just went on full power all the time, the only header it actually worked on was the CPU header.

Only the CPU header had the speed control wire on pin 4, the other headers have it on pin 2, the others had voltage control on pin 4. I just run a few splitters from my headers and use a few splitters on the hub and im using nearly double the amount of fans as yourself, personally splitting up the controls works better for me as i have fans coming on at different temps, i dont want 20+ fans all just coming on together. Maybe the wire can just be moved to pin 2 but i wouldnt want to say as i dont know how fan wires work.
Click to expand...

Well that's seriously bloody annoying! I specifically looked up the fan situation with the mobo so I guess I misinterpreted what I was reading or found some bad info. How are you powering that many fans and keeping control of them? Some from each fan header and some from the hub? Does the hub give you the same level of control as the fan headers and how many amps can it put out through each connector?
 
Fan control on pin 2 means voltage control only. You can't swap wires to 4.

The PWM hub mentioned is a controller for 3 pin voltage controlled fans that can be controlled by a valid PWM signal.

I would think that having quite so many PWM fans on a single PWM signal source may be a problem. Some fans load down the signal, some Corsair fans are known for this.
 
Had exactly the same issue - planned to use an Akasa Flexa cable to control some fans, turned out the motherboard headers didn't support PWM.

I solved it by adding a small DC-DC buck converter between the power connector of the Flexa cable and PSU. It's not the prettiest solution (I just bought a cheap eBay converter) but it lets me easily control all five fans with a single potentiometer.
 
Mark_D said:
Well that's seriously bloody annoying! I specifically looked up the fan situation with the mobo so I guess I misinterpreted what I was reading or found some bad info. How are you powering that many fans and keeping control of them? Some from each fan header and some from the hub? Does the hub give you the same level of control as the fan headers and how many amps can it put out through each connector?
Click to expand...

I just use all the headers, i basically have about 10 fans coming off the hub using a few splitters onto the CPU header, then i have spread the rest out between OPT fan1,2,3 dont use 4 at thats 100% with no control if its the same as the z97 board. So with the other 4 headers im using 3 way splitter cables.

I control the fans all using speed fan, ive set up most of the fans to run according to my GPU sensors but you can set them to run from any sensors. Then main reason i like lots of groups is so i can tell more fans to turn on the hotter the GPUs get, so i just have my 480 rad come on first with some low noise fans, then the 360 next as things get hotter then finally the 2 240s fire up as the GPUs get into late 40s and stop them around 50 degrees and the loop levels out at that temp.

Btw have you tried using the fan controller without the extra sata power? my hub would worked ok without the exta power, but i just had to use less fans.
Have a look at your manual there will be a list of hte headers and it will tell you what each header supports, maybe aon the z170 theyre all different so ya dont wanna go off what im saying really.
 
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Unplugging the SATA power had actually crossed my mind funnily enough. Having four on each header pulling at least 1.2A was what stopped me. I don't know what the headers are rated for as the manual doesn't say. For some reason I have a figure of 1A stuck in my head. Can anybody confirm or deny?
 
1A is usually about right. Also keep in mind that most fans 'rated load' is running load, not startup load .. and startup load is 2-5 times more than running load. This means a 0.2A rating on the fan could easily draw 0.5-1.0A at startup. Startup load is same as stall load .. fan drawing power but not turning.
 
OK so a fan controller is probably the easiest solution as long as I can find one which will do the job.
 
You could try all of your fans on a couple of PWM hubs with PSU power using a PWM 'Y' splitter to supply both hubs with PWM signal. With most all PWM fans, 8 fans can be controlled with a single PWM signal, but I have had as many as 13 PWM fans working on a single PWM signal.

I don't know what the DC-DC buck converter kaku used looks like, but I have seen and almost ordered a little temperature controlled PWM controller off of fleabay just to try it out. Came with it's own temp probe and had what looked like decent temp to PWM% curve settings. Try searching for 'temperature controlled pwm controller' and see what you get. The one I was looking at is 5.95 with a green PCB and digital readout.
 
For those sorts of prices those Chinese boards provide a good solution. The only issue is calibrating the thermistor to your components.
 
@Tealc, The instructions do not give a lot of details so not sure how functional the temp to PWM signal curve would be. I can give you a link to them if you are interested.
 
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