Question BIOS Fan Speed on ASUS B650M TUF motherboard ?

[frogon]

I have an ASUS B650M TUF motherboard with one CPU and one case fan and used ASUS Q-Fan to set the fan curves so they are somewhat quiet. Using Libre Hardware Monitor inside Windows 10 I am seeing (and hearing) the actual fan speeds are not following the fan curves, but I do not have any other fan control software installed. The case fan (fan #1) and cpu (fan #2) are going down their idle speeds but seem to increase speed based on cpu usage and not the cpu temp. This results in the fan speeds ramping up and down every time the cpu load increases, rather than slowly as the temp rises.

I asked over on the ASUS forums and did not get a response. here's the images of the fan curves and then an example where the current fan speeds are running 50% at 34C when they should be closer to half that.

I only set the fan speed in the BIOS, no other controlling software installed in windows 10. What is causing the fan speeds to not follow the fan curves?

cpu curve:
20C 22%
45C 40%
65C 70%
70C 100%

cha1 curve:
33C 11%
50C 40%
65C 70%
70C 100%

 

[Lutfij]

Welcome to the forums, newcomer!

Looking through Libre Hardware Monitor's screenshot, is this;

TUF GAMING B650M-PLUS WIFI｜Motherboards｜ASUS Global

TUF Gaming series distills essential elements of the latest AMD and Intel® platforms, and combines them with game-ready features and proven durability. Engineered with military-grade components, an upgraded power solution and a comprehensive set of cooling options, this motherboard delivers...

www.asus.com

the motherboard you're working with? My understanding would be that the software is sensing the VRM's getting hot and asking for more airflow across said VRM's heatsinks. Out of curiosity, what BIOS version are you on?

As for the specs to your build, please list them like so:
CPU:
CPU cooler:
Motherboard:
Ram:
SSD/HDD:
GPU:
PSU:
Chassis:

Make and model of the chassis fan(in case it didn't come bundled with the case) If the fan came bundled with the case then mentioning the case's make and model is fine.

 

[frogon]

Welcome to the forums, newcomer!

Looking through Libre Hardware Monitor's screenshot, is this;

TUF GAMING B650M-PLUS WIFI｜Motherboards｜ASUS Global

TUF Gaming series distills essential elements of the latest AMD and Intel® platforms, and combines them with game-ready features and proven durability. Engineered with military-grade components, an upgraded power solution and a comprehensive set of cooling options, this motherboard delivers...

www.asus.com

the motherboard you're working with? My understanding would be that the software is sensing the VRM's getting hot and asking for more airflow across said VRM's heatsinks. Out of curiosity, what BIOS version are you on?

As for the specs to your build, please list them like so:
CPU:
CPU cooler:
Motherboard:
Ram:
SSD/HDD:
GPU:
PSU:
Chassis:

Make and model of the chassis fan(in case it didn't come bundled with the case) If the fan came bundled with the case then mentioning the case's make and model is fine.

PC Build:
CPU: AMD Ryzen 5 9600X
CPU cooler: Cooler Master Hyper 212
Motherboard: ASUS TUF B650M-PLUS Gaming Wifi
Ram: G.Skill Flare X5 16gb ddr5-6000 single stick
SSD/HDD: 1tb + 2tb M2 drives
GPU: MSI 4070 Ventus 2x (2 fan)
PSU: Lian Li SP 750watt SFX
Chassis: Lian Li A3
Extra chassis fan: Lian Li Uni P28 120mm

I'm on BIOS 3024, I checked the change log and in 3067 they added "2.Fixed a few fan-related bugs and improved overall system performance." I will update and see if I see a difference.

 

[CountMike]

PC Build:
CPU: AMD Ryzen 5 9600X
CPU cooler: Cooler Master Hyper 212
Motherboard: ASUS TUF B650M-PLUS Gaming Wifi
Ram: G.Skill Flare X5 16gb ddr5-6000 single stick
SSD/HDD: 1tb + 2tb M2 drives
GPU: MSI 4070 Ventus 2x (2 fan)
PSU: Lian Li SP 750watt SFX
Chassis: Lian Li A3
Extra chassis fan: Lian Li Uni P28 120mm

I'm on BIOS 3024, I checked the change log and in 3067 they added "2.Fixed a few fan-related bugs and improved overall system performance." I will update and see if I see a difference.

Instead of Autodetect make sure it's set same as actual fans are.PWM or Voltage regulation.
Another thing is that fan speed is pretty imprecise, to start with it's up to +/- 10% of stated rpm between two of them and usually more than +/- 200 to 300 rpm at any speed even for PWM fans so no use fussing too much with speed curves. Just a straight line between minimum and maximum is good enough.

 

[frogon]

Instead of Autodetect make sure it's set same as actual fans are.PWM or Voltage regulation.
Another thing is that fan speed is pretty imprecise, to start with it's up to +/- 10% of stated rpm between two of them and usually more than +/- 200 to 300 rpm at any speed even for PWM fans so no use fussing too much with speed curves. Just a straight line between minimum and maximum is good enough.

I'm not really concerned about it being exactly 30% speed, I'm more curious at why the fans will suddenly spin up to 50% and then back down when the CPU temp is exactly the same. Its "ok" but its kind of annoying since it happens almost every time I open a big app like Steam and the A3 case is full mesh so its pretty easy to hear. I logged the fan and cpu temp data of me opening up steam and iracing at the same time, you can see the fans ramp up and back down in 20 seconds while the CPU temp stays the same.

if it is that the VRM temps are getting high as @Lutfij suggests then I guess the solution would be to increase fan idle speeds?