Help properly installing and managing fans

[asendra]

So, I changed my case recently to a Fractal Design Nano S (No window). The temperatures are perfectly ok (27 idle, 45-55 gaming, 60-70 prime95), I just have too much sound due to not being able to control the fan speed properly.

My motherboard (ITX) only has 2 fan headers, CPU and SYS.

Currently my setup is as follows:
- 2 Noctua NF-A14 on the from as intakes
- On the top front fan, I have an Corsair H80i v2 (120mm) AIO with an 140 to 120mm fan adapter, and a SP120 fan that came with the AIO as exhaust (for a push-pull config)
- On the back, I have the other SP120 fan that came with the AIO as exhasust
- On the bottom, I have a fractal 120mm fan as intake (no PWM)

Right now the push-pull fans are connected to the AIO, which is connected to the CPU fan header and controlled through iCue.
The other three are connected via splitter to the other SYS fan header, controlled my the motherboard (can get Speedfan to control them? ...).

Questions and observations:
- I really prefer my AIO as intake and I would love to keep using my Noctua fans so thats why the 140 to 120mm fan adapter. It may sound whacky, but I think it doesn't affect performance.
- My theory is that if all fans in a header are PWM, even if they are different, it should work ok (obviously at different RPMs each) Correct?
- I need to buy a 120mm fan to change the non PWM one. I might change the corsair ones if I can't get them under control sound wise through PWM (they go up to 2435 rpms...)
- I would prefer to just use one software, but iCue can only manage the fans connected to it..
Option 1 is connect all fans via splitters to the AIO
Option 2 is use another software to control all of them and remove iCue
Option 3, use iCue for the Push-Pull fans on the AIO, use another program for the other 3 case fans..

 

[Freddy1765]

What kind of motherboard do you have? Some manufacturers provide software to manage things like fans from the OS (e.g. Asus AI Suite). It may also be possible to do so from the BIOS. Note that the SYS header is most likely not PWM (my Maximus VII Hero has like 4 4pin SYS headers and none of them are PWM), so you would need to use splitters from the CPU header for your PWM fans.

In such a small case it really seems like massive overkill to have 5 fans. More is not necessarily better, and you're going to hit diminishing returns pretty quickly.
I would consider removing the bottom intake and the SP120 you have on the radiator.
In my experience bottom intakes don't provide much benefit, assuming proper front intakes. I don't know how much the radiator heats/restricts the air going through it, but if you have a Noctua on the bottom lined up with the GPU + the intake on the AIO and a rear exhaust, I'd say you're golden.
I've got two NF-A14 intakes, one NF-A14 top exhaust and an NF-A12 rear exhaust in my Meshify C (1070Ti and 4790k) which provides great temps at very reasonable noise-levels.

 

[Paperdoc]

You are correct in saying that it can all work IF all the fans on one mobo fan header are the same type AND that header can be configured to use the correct control Mode (either Voltage Control (aka DC Mode) or PWM.

I expect that the two fans on the radiator are connected properly to the cable coming out of the pump unit, and that those fans are the ones supplied with your H80i system. So those fans will be controlled by iCUe. BUT be SURE that, in doing the installation, you conneted a cable from a port on the pump unit to a mobo USB2 header. This is how the iCue software can communicate with the H80i system. Using that software will allow you to adjust and observe the opereations of the H80i system. Does it show your pump and fan speeds? Does it allow you to change the fan speeds? Can you verify that the fan speeds actually DO change when you change their settings in iCue?

From what you describe there is only one "problem" fan, the one on the bottom which is NOT PWM. You have it plus two Noctua fans connected using a Splitter to the only SYS_FAN header available to you. You have not specified, but I assume the Noctua units you have are the 4-pin (PWM type) version, not the similar 3-pin models. Now, if you connect a 3-pin fan to a header that uses the new PWM Mode for control, that fan will always run full speed. So, if I understand your system correctly, all the other fans CAN have their speed changed. The two on the radiator will be adjusted via iCue, and the two Noctua case fans can have their speed altered by the settings for the mobo SYS_FAN header. Only the bottom 3-pin fan never changes speed. Is that all correct?

Your best solution is to replace that bottom fan with a 4-pin (PWM) fan and use your Option 3. You do NOT need other software. With the arrangement you have the ONLY way to control speeds of your three case fans is through the SYS_FAN header, and that can ONLY be done if that header is using the correct MODE to exercise control. Since you are already using PWM Mode there because of the Noctua fans, that Mode cannot control the 3-pin fan and it needs replacement.

There MAY be one other option that is free. Because of backwards compatibility, the 4-pin (Noctua) fans CAN be controlled by the older Voltage Control Mode (aka DC Mode) that is needed to control the 3-pin fan. This is not quite as good as the PWM Mode for those 4-pin fans, but the difference is minor. So IF your mobo SYS_FAN header has an option to change its Mode to Voltage Control Mode, that would bring all three of those fans under control. By the way, this latter idea can only work if the device you are using really is a SPLITTER. There are very similar devices called HUBS that often are mis-labelled as Splitters but ONLY work with 4-pin fan systems. The difference is that a HUB has one arm with a big connector on the end that must be plugged into a 4-pin Molex or SATA power output connector from the PSU. If your device does NOT have that extra "arm", it is a Splitter and this configuration change can work.