[SOLVED] fan speed only work in BIOS

[usace]

All my case fans are stuck at max speed. The setup: Ryzen 3600 on ASRock B450m Steel Legend with 3 three-pin case fans plugged into the four-pin headers. While in the BIOS I set the fans to read mb temp and use a quiet fan profile, and I alll the fans slow down and work great until I reboot into the OS. Then all the fans spool up to 100% speed and never stop. I tried the A-Tuning software but it had no effect and during the calibration step it measured the same RPM at all power levels. I uninstalled that software thinking it could conflict with the BIOS setting, but am still having the same issue. I have tried using a 4 pin fan and all the headers can control the speed of that outside the BIOS. But for my three pin fans it only works while in the BIOS.

 

[Darkbreeze]

Are you setting those fan headers in the BIOS, individually, to DC mode, or leaving them on PWM mode? They MUST be set to DC mode in order to have variable controlled speed otherwise they will just default to full speed operation.

 

[usace]

Are you setting those fan headers in the BIOS, individually, to DC mode, or leaving them on PWM mode? They MUST be set to DC mode in order to have variable controlled speed otherwise they will just default to full speed operation.

At first they were set to AUTO, then I manually set them all to DC mode. They still worked in BIOS but then went full speed upon exiting

 

[Darkbreeze]

Are you going to the exit tab in the BIOS and saving the settings?

Are the keyways on the three pin connectors lined up with the key on the fan headers?

Personally, I'd recommend that you check to see that you have the MOST recent BIOS version installed, as there may have been more a more recent release than what you have installed. The latest release was today, version 2.6. Also, you should make sure you have the latest AMD chipset drivers installed using the AMD All in one driver setup package.

After updating, I would do a hard reset of the BIOS and then reconfigure your settings. It sounds like the BIOS is "stuck".

Power off the unit, switch the PSU off and unplug the PSU cord from either the wall or the power supply.

Remove the motherboard CMOS battery for five minutes. In some cases it may be necessary to remove the graphics card to access the CMOS battery.

During that five minutes, press the power button on the case for 30 seconds. After the five minutes is up, reinstall the CMOS battery making sure to insert it with the correct side up just as it came out.

If you had to remove the graphics card you can now reinstall it, but remember to reconnect your power cables if there were any attached to it as well as your display cable.

Now, plug the power supply cable back in, switch the PSU back on and power up the system. It should display the POST screen and the options to enter CMOS/BIOS setup. Enter the bios setup program and reconfigure the boot settings for either the Windows boot manager or for legacy systems, the drive your OS is installed on if necessary.

Save settings and exit. If the system will POST and boot then you can move forward from there including going back into the bios and configuring any other custom settings you may need to configure such as Memory XMP profile settings, custom fan profile settings or other specific settings you may have previously had configured that were wiped out by resetting the CMOS.

In some cases it may be necessary when you go into the BIOS after a reset, to load the Optimal default or Default values and then save settings, to actually get the hardware tables to reset in the boot manager.

 

[usace]

Thanks for the suggestions, I tried many of them over the past week but the one thing that ended up fixing it was to install the latest bios V 2.6. I'm not sure if it needed a bios reset or if there was some bug fix from the latest bits, but going through the update process fixed the issue! Now my PC is nice and quiet and I have full control of the fans using the A-tuning software or the bios.

 

[Darkbreeze]

Perfect man. That's what we were hoping for. Glad it worked out for you.