Case fans connectivity and control

[Harris69]

I have a Kolink AVIATOR case with 3 pre-installed fans that connect to a fan controller on the case and they are powered by a molex connector. I have a ASUS Z170 A Mobo and these fans are not showing up in the BIOS, the only fan running according to the BIOS is the CPU fan. how can I control fan speeds if I can't see them in the BIOS?

 

[smorizio]

the fan controller on most cases are dumb. there a large resitor in the switch so that your chaning the voltage to the fan when you chnage the fan speed on the case. you would have to replace those fans with pmw 4 pin fans if your fan headers are 4 pins and you want the mb to control the speed. i would not use case fans as is. they may pull more power then your mb can give i would look at 3 party low power case fans. if you want the mb to run them.

 

[michaelzehr]

Just had a similar situation in a build using a Phanteks Enthoo PH-ES614P_BK case. The manual was a little vague, but indicated that the motherboard would only see one fan, and would control them all at the same rpm (I'm not sure if that's the same rpm, or the same % rpm if they had different maximums -- one of the ways the manual was vague). (Phanteks calls it a PWM hub -- it looks similar to the one on the kolink other than molex vs. sata power connector. But either way, you should be getting enough power for all the fans from the molex -- it shouldn't be pulling power from the m-board.)

We haven't decided yet if we're going to keep using it as it or get a separate fan controller.

Short story is I think you can control them, but not individually.

 

[Paperdoc]

The first and third posts above actually are two very different systems.

First one. Your case has all its fans under the control of a controller in the case, and all their power comes from the PSU. That controller will allow you to set MANUALLY what speed those case fans run - maybe only using words like "Hi, Med, Lo". There is NO communication between those fans and your mobo, so the mobo does not even know they exist. The mobo cannot tell you anything about them, and can NOT control them at all.

IF you want your case fans under automatic mobo-based control you will have to replace them. But before you do that, post back here exactly what mobo you have. Then we can look up its fan control details and tell you what KIND of fan you need. Post also how many such fans you plan, so we can advise how to connect them.

Third post: you have a Phanteks case that includes their PWM Hub. This Hub requires a PWM signal input from a mobo fan header that actually uses PWM Mode for control, and then it uses that to power and control all the fans plugged into it. To do that, it also requires that you plug a cable into a SATA power output connector from the PSU. It is a unique Hub in one important way. Most such Hubs only share the PWM signal to their fans, and that means they can only control 4-pin fans. But the Phanteks PWM Hub uses the PWM signal from the mobo header to create its own group of 3-pin output ports using Voltage Control Mode, and that system can power and control any mix of both 3-pin and 4-pin fans. The Hub's instructions try to prevent a problem some people have with odd mobo ports. So they tell you you must plug its input connector into the CPU_FAN mobo header, because that one is SURE to provide the PWM signal it needs. That also means that you MUST plug the actual CPU cooling fan into the WHITE Port #1 of the Hub, and other fans in other ports. That Port #1 is the only one that can send its fan's speed signal back to the mobo CPU_FAN header, and it is important for your system's protection that it monitor the CPU cooling fan.

 

[michaelzehr]

The first and third posts above actually are two very different systems.
...

Thank you, I certainly didn't glean that much info from the case manual.

My son and I stared at it for a while, and eventually plugged his liquid cpu cooler into cpu-fan header, and the phanteks hub into one of the cha-fan headers, because we wanted to be sure the mobo was indeed controlling the cpu cooler... and since the cpu cooler has it's own sata power connector, and the pwm hub also has one, we weren't sure if they would play nice together.

(Then the corsair link program messed around with it, but I think he has it configured now.)

 

[Paperdoc]

OK, from those comments I assume the liquid cooler system you have is one of the Corsair models. Which one?

Now, using the Phanteks PWM Hub with a mobo CHA_FAN header is OK in SOME cases, and that is not what the Phanteks instructions say. It is OK ONLY if the mobo header you use does use PWM Mode to control its fan(s), and you cannot tell about that merely from the pin count on the header. That info is deduced from the mobo manual's details. So post back here the exact mobo maker and model, and we can advise whether this should work. In the meantime, what do you observe? Do the speeds of the fans you have connected to the Hub actually change?

 

[michaelzehr]

OK, from those comments I assume the liquid cooler system you have is one of the Corsair models. Which one?

Now, using the Phanteks PWM Hub with a mobo CHA_FAN header is OK in SOME cases, and that is not what the Phanteks instructions say. It is OK ONLY if the mobo header you use does use PWM Mode to control its fan(s), and you cannot tell about that merely from the pin count on the header. That info is deduced from the mobo manual's details. So post back here the exact mobo maker and model, and we can advise whether this should work. In the meantime, what do you observe? Do the speeds of the fans you have connected to the Hub actually change?

He has an Asus Z170 pro gaming. The manual says that the cha_fan headers work in either dc or pwm mode. I will have to check that my son set them to pwm in the bios and that this wasn't overridden by any of the other fan tools.
I've had him watching the temperatures pretty closely. He diagnosed and fixed one problem that corsair link had been set to silent (30% max) and he got some cpu thermal throttling after playing an hour or more of some VR game. He says he's not getting any GPU thermal throttling (he has a 1080). I'm considering getting another/bigger fan just on general principles that cooler systems last longer. I haven't asked him how he's set the two case fans and whether they are speeding up with increasing internal temperatures.

I don't think he has overclocked his cpu yet (core i7 6700k) and he briefly overclocked his GPU but then put it back to default (GIGABYTE GeForce GTX 1080 XTREME), but on that I don't know which mode he normally runs it in of the factory OC settings (normal/gaming/oc I think they're called).

The cpu cooler is a Corsair Hydro Series H115i.

 

[Paperdoc]

You are correct about the mobo header capabilities, and also right to check closely the BIOS Setup configuration for the mobo CHA_FAN headers. Firstly, the manual says they arrive set to DC Mode by default, so changing to PWM Mode will be necessary to get the Phanteks PWM Hub to work. Secondly, the manual says also that the default "Q-Fan Source" for these headers is "CPU" but you should change that to "MotherBoard" to ensure that the case ventilation fan control is based on the temperature measured on the mobo, and not inside the CPU chip.

I also agree with your concern about the "silent" fan configuration. I see too many people who do not understand that "silent" means forcing the fan(s) to run at a fixed slow speed for quiet operation, BUT that means also MUCH reduced air flow and inadequate cooling when the workload increases. I always prefer to let the automatic control system run normally to use the full range of fan speeds. That way the fans will be quiet when you're doing little, and will speed up to whatever is needed when you stress the system with games etc.