[SOLVED] Asus mobo Qfan control

Apr 16, 2019
31
0
40
Today i tried to make my pc quiet, but i ran into something weird.I was using asus Qfan control, from my mobo's bios.Thing is that while 2 fans were spinning at around 900 rpm (not 100% sure, it's just what is displayed in the bios) the other two are at 2700 and 2900 rpm.I expect it's because im using Qfan control wrong, but i would prefer to use something else.Can someone tell me how to fix the problem/advice a software for fan control?
 
Solution
Thanks for that info. See your mobo manual, p. 1-17. The mobo has three slightly different types of fan headers. The CPU_FAN and CPU_OPT headers are both tied to the temperature sensor inside the CPU chip, and both can be configured to operate separately in BIOS Setup. The three CHA_FANn headers are tied to a different temperature sensor built into the mobo. Each can be configured separately, and they are the ones you should use for case ventilation fans. The AIO_PUMP and W_PUMP+ headers are intended to power only the pump unit of a liquid-filled CPU cooling system, and so they do NOT generally allow you to control their speeds at all - they are supposed to run the pump at full speed all the time. So do NOT use those last two for any...

Paperdoc

Polypheme
Ambassador
To help you we need more info.

  1. Exactly what model number of ASUS mobo do you have?
  2. You have 4 fans. Tell us the maker and model number of each. If you can't get that, at least tell us how many wires are in the cables from the fan motor to the connector for each (and thus, how many holes are in the connector).
  3. Tell us exactly where each fan is plugged in.
 

Paperdoc

Polypheme
Ambassador
Thanks for that info. See your mobo manual, p. 1-17. The mobo has three slightly different types of fan headers. The CPU_FAN and CPU_OPT headers are both tied to the temperature sensor inside the CPU chip, and both can be configured to operate separately in BIOS Setup. The three CHA_FANn headers are tied to a different temperature sensor built into the mobo. Each can be configured separately, and they are the ones you should use for case ventilation fans. The AIO_PUMP and W_PUMP+ headers are intended to power only the pump unit of a liquid-filled CPU cooling system, and so they do NOT generally allow you to control their speeds at all - they are supposed to run the pump at full speed all the time. So do NOT use those last two for any fans.

Now look at p. 3-7 where the general layout of a fan header configuration screen is shown. There is no detail on each screen, but this will do. First, you have a small dilemma - four fans, but three headers suited to controlling them. So you need a simple two-output SPLITTER like this

https://www.newegg.com/p/N82E168124..._re=Coboc_fan_splitter-_-12-423-160-_-Product

A version with 12" arms also is available. NOTE that this device has only two types or "arms". One ends in a female fan connector with 4 holes to plug into a mobo header. Two arms (on this model) end in male (with pins) outputs to plug in your fans. There are NO other types of arms. Some makers sell a different item they may call a Splitter, but which I label a HUB, which can come in various forms including a simple group of arms like this. But what makes them different is that they have a third "arm" that must plug into a power output connector (either 4-pin Molex or SATA) from the PSU to get power to the Hub. To connect two fans to one header you do not need that Hub, so just get a Splitter. Also note one other factor when using such devices. A mobo fan header can deal with the speed signal coming back to it from only ONE fan. So a Splitter or a Hub will send back only one fan's speed signal and ignore all the rest on that Splitter. This has NO effect on the ability to control speeds. But it does mean that your mobo will never "see" the speed of the second fan on the Splitter so you won't, either. The way that is accomplished is that one of the output male connectors is missing Pin #3 so that fan's speed is NOT connected back to the host header.

So, connect two of your fans' motor leads to the Splitter, and that into one CHA_FAN header. The other two fans can go to the remaining two CHA_FAN headers. I gather you realize that the RGB lighting cables from each fan are connected to other places.

Now go into BIOS Setup and refer to p. 3-7. You need to configure each of those three headers. For each, select the header. At top right ensure it is set to PWM Mode for your 4-pin fans. Unless you have a particular need and know how, do not bother with custom settings. Simply choose the "Standard" Profile at the bottom, then proceed to the next header. By the way, exactly the same settings are best for your CPU_FAN header, too. When done, use Esc to return to the Main Menu (p.3-3), and then the F10 key to get to the Exit Menu (p. 3-19). Choose the SAVE CHANGES & RESET item to save and reboot your machine with these new settings.

To observe fan speeds, you can use the BIOS Setup screens, but they cannot be seen when you are actually working. However, on the CD that came with your mobo there are many utilities, and one of them will include a QFAN tool you can run as an application under Windows so it can be on your screen with other stuff while you work. This tool shows you fan details and will allow you to change them if you need to. It is calibrated for your mobo so will show you correct readings.
 
Solution