Front Fans Cooler Master H500P Mesh don't appear in Bios

[Amdregaz]

Hi guys, I have a problem with the 2 front RGB Fans that come with the case.
My motherboard Asus x470 Prime doesn't show me their RPM, it shows that their N/A although they spin and I can control them in DC mode.
The problem is that I can't set them below 60% duty cycle. After I ran the optimization fan utility in bios it allowed me to set the duty cycle of the rear fan to 27%.
So I think this should work for the front fans as well but the motherboard doesn't read them and I do have the latest bios.
Also all the case fans are 3 pin fans and the front fans connect to some adapter which has 3 heads of 2 pins each (1 is vacant and the other 2 I've plugged the front fans) and then it goes to the motherboard with a 3 pin connection. I don't know maybe this is the problem or I haven't connected them properly.
How can I get the front fans to be read in bios?
Thank you.

 

[Lucky_SLS]

The problem with 3 pin fans is that the voltage varies from 5 to 12 volts. 4 pin fans get a 12v constant and also has a pulse wave to control the current, hence modifying the speed (maybe I am not saying it right but you can grasp the basic idea)

So if the voltage drops below 5v in 3pin, the fan stalls. And I think in this particular case, the 5v input gives 60% speed of that 800rpm for those front fans.

 

[Amdregaz]

The problem with 3 pin fans is that the voltage varies from 5 to 12 volts. 4 pin fans get a 12v constant and also has a pulse wave to control the current, hence modifying the speed (maybe I am not saying it right but you can grasp the basic idea)

So if the voltage drops below 5v in 3pin, the fan stalls. And I think in this particular case, the 5v input gives 60% speed of that 800rpm for those front fans.

It's true the rear one stayed around 800 Rpm when set to 60%
But the problem is that the front fans aren't read in Bios, if I could get them to be read I'm sure the Asus Fanxpert would let me use them under 60%

 

[Lucky_SLS]

think u misunderstood, what i actually meant was the front fans max rpm is 800. so 60% of 800 is 480rpm. the rear case fan max is about 1200 or 1500? 27% of that is around 380rpm.

so what my guess is at 5v(min. setting, ranges from 5 to 12v like i said in the above post for 3 pin fans), the front 200mm fans can be run at 60% load or 480rpm and the rear fans at 5v is 27% load or ~380rpm.

 

[Amdregaz]

think u misunderstood, what i actually meant was the front fans max rpm is 800. so 60% of 800 is 480rpm. the rear case fan max is about 1200 or 1500? 27% of that is around 380rpm.

so what my guess is at 5v(min. setting, ranges from 5 to 12v like i said in the above post for 3 pin fans), the front 200mm fans can be run at 60% load or 480rpm and the rear fans at 5v is 27% load or ~380rpm.

Still why won't they appear in bios like the rear one?

 

[Lucky_SLS]

Try using a splitter for the front fans and connect them to a voltage control header. The issue maybe is with that fan hub you have currently connected to.

 

[Amdregaz]

Try using a splitter for the front fans and connect them to a voltage control header. The issue maybe is with that fan hub you have currently connected to.

I don't have a hub, I have a fan splitter (sorry I didn't knew what's the name) like the one in the first photo

https://www.aliexpress.com/store/product/12V-3-Pin-Fan-PWM-1-to-2-way-Power-supply-Extension-Cable-Y-Splitter-Port/710969_32794637126.html

Except mine is a 3 way with 2 pins at each end and a 3 pin that binds them all and goes into the motherboard.
I'm not using all 3, just 2 for the front fans.

If I buy a 4 pin with a 2 way (3 pins) will I be able to see the fans in bios?

https://www.amazon.co.uk/Akasa-AK-CBFA04-15-Splitter-Cable-Fans/dp/B005FWXWPS/ref=sr_1_2?ie=UTF8&qid=1542438405&sr=8-2&keywords=2+way+fan+splitter

 

[Lucky_SLS]

simple answer : connect 1 fan to ur mobo voltage control fan header and see if it gets detected and if u can control it. if thats a ok, see the pin configuration and see if the linked above splitters can take those pins/compatible with it.

ur mobo manual would have info abt the fan header along with which of the 3 pin is a ground, voltage source.

 

[Amdregaz]

I bought this and it solved my problem, the fans appear now in Bios and the optimizing from Asus let me to set them to 26% duty cycle