Can't Control CPU Fan Speeds

[Zack Brown]

Specs:
i7-6700K
AMD R9 390
ASUS Z170-A
Corsair H110i GTX (replaced stock fans with Silent Wings 2 140mm PWM)
Corsair Vengeance 16GB 3000MHz DDR4

Before I replaced the fans on the radiators from the stock ones to the Silent Wings 2, I could control the fan speeds in Corsair Link without a problem.
After replacing them, I could no longer control the fans, even though the wiring is exactly the same as it was before.

1.The two Silent Wings 2 PWM 140mm fans are connected to a splitter that is connected to the AIO cooler. (One connector has 3 pins and the other has 4 pins. Both fans have 4 pins).
2. The AIO cooler also has a SATA cable that is connected to a SATA port.
3. The AIO cooler has a 3 pin connector that is connected to a 4 pin CPU_FAN header (the CPU_FAN header only gives RPM data to the computer).
4.The AIO cooler has a mini-USB cable that is connected to a USB 2.0 connector.

Corsair Link shows MB fan is spinning at 770-890 RPM
AI Suite 3 shows CPU fan is spinning at 770-890 RPM
Both are referring to the same fans.
Ideas?

 

[atknatmrt]

I think that your splitter may be the problem keep in mind that 3 pin connectors don't support pwm control they only support voltage control.

 

[Zack Brown]

I think that your splitter may be the problem keep in mind that 3 pin connectors don't support pwm control they only support voltage control.

I thought so too, but the thing is it worked with the stock fans.

 

[devbiker]

You control the radiator fans in Link by going to the fans connected to the cooler. The MB fan is actually showing a value related (loosely) to Pump RPM. It's a reading only; there's no control for the pump or the fans there.

Link has never been able to control fans connected to the motherboard. And motherboard fan readings aren't going to be reflecting of the fan speed on the radiator. You'll get that completely from Link.

 

[Paperdoc]

OP, your point #2 says the pump has a cable connected to a SATA port. I suspect strongly that it is plugged into a SATA power output connector from the PSU, and NOT into a mobo SATA port. Is that right?

atknatmrt has the splitter thing wrong. On any fan, Pin #3 is the speed signal generated by the fan and sent back to the mobo on this pin. The mobo header can only deal with a speed signal from ONE fan. So, any proper Splitter will send back to the mobo header the speed signal from only one fan; the most common way to do this is to omit Pin #3 from the male output for the other fan on the two-output splitter. For a 4-pin fan (PWM type), the other wires are Pin #1 Ground, Pin #2 fixed +12 VDC, pin #4 PWM signal. With those three signals on those pins, the fan DOES receive power and WILL be under speed control IF the source of the fan signals is actually sending out a PWM signal for it to use.

This all sounds like the Corsair Link software is NOT sending out proper signals to the system. Those speeds you report in Corsair Link and AI Suite3 both appear to be the PUMP speed of your system - that is what the cable from the pump to the CPU_FAN header sends there. Corsair Link is supposed to detect and report the speeds of the RADIATOR fans separately through its USB connection to the pump. You have not told us what Corsair Link says about the RADIATOR fan speeds.

Before going any further, re-check all your connections. Be sure that the cable from the pump to the USB mobo header is connected well. If this does not help, proceed below.

You can try this to reset things. This will temporarily shut down Corsair Link. In that situation the H110i system will run the radiator fans at full speed all the time (which is what you get now) so your CPU WILL still have good cooling - in fact, too much.
1. Un-install Corsair Link.
2. Shut down and disconnect the cable from the pump to your USB header.
3. Boot up and verify things are working. Check and maybe re-install the USB drivers for your mobo.
4. Shut down. Re-connect the USB cable from pump to mobo.
5. Boot up. Install Corsair Link once again.

This might get Corsair Link to recognize all your components and work correctly.

Another check you can do would be to connect any other 4-pin fans (even the originals) to the Radiator fan cable, in place of those fans. You do not need to change the fans on the radiator. For a short test run of a few minutes, the system can run with NO fans working on the Radiator, just the pump running the liquid around the cooling loop. See if the "other" fans' speeds are under control or not. Then shut down and re-connect the fans that ARE on the radiator.

 

[devbiker]

First, the splitter is fine. One of the fans is missing the speed control pin. As Paperdoc points out, this is correct.

Second, the pump is connected to the CPU Fan header. It reports the pump speeds. Not the fan speeds.

Link doesn't send out the signals; the micro processor in the pump does that. Link reports the readings and sets the fan curves. By default, the fan curve is based on the coolant temperature and this runs entirely within the pump's MPU. If, however, you set Link to use another temperature as the control for the fan curve, then Link will have to continuously update the pump's MPU with the target fan speed. Don't do this.

When not running Link, the cooler runs the default profile that's stored in the MPU. You can actually overwrite this with most coolers by going to Options ... Devices ... "Use current settings as default". It does not run the fans at 100%. Unless you set your fan curve source temperature to something that's other than the pump's coolant temperature ... then it might. But ... like I said, don't do that.