Question Case fan control setting works in bios but failed when get into windows10

Sep 4, 2019
6
0
10
3-pin case fans are connected on sys-fan header
Fan speed is normal during boot or in bios.
When it enters windows 10 , the case fans go to 100% speed and it is so loud. How can I fix this?
I have tried change setting in SIV app made by gigabyte, updated bios
SIV is crap. Fans can be turn off when I use discovery mode searching fan inside SIV app, but the controlling curve doesn't work

Motherboard : gigabyte Z170-D3H
 
Sep 4, 2019
6
0
10
Try uninstalling the SIV app as the BIOS and that will clash if they have different settings applies.
Once it is uninstalled your case fans should run at the settings in your BIOS.

Andy
My PSU had problem, I bought new one and replaced it.
After that, the case fan always go 100% when enters windows.
SIV was not installed that time.
I tried uninstall SIV then, it still go wild
 

Paperdoc

Polypheme
Ambassador
You have 3-pin fans, so their speed can be controlled ONLY by a SYS_FAN header that uses the older Voltage Control Mode (aka DC Mode), and NOT by the newer PWM Mode. Now, the manual for your mobo indicates that its three SYS_FAN headers only do the older DC Mode with no option for PWM, so that SHOULD work. BUT if your mobo is a more recent version that does use (or at least allow) PWM Mode, then that could cause the fans to run full speed all the time.

The other possibility is that somehow your SYS_FAN headers were configured to use constant Full Speed, rather than Normal automatic speed control. This MIGHT have happened if your problems and fixes resulted in a BIOS Reset,

Go into BIOS Setup to where the three SYS_FAN headers are configured - see manual p. 25. For EACH of them, check and set these items.
nth System Fan Speed Control set to Normal
IF there is any choice about fan control MODE, ensure it is set to DC or Voltage, and NOT to PWM

After you have made all your changes for those three, use Esc to return to the main menu, then choose SAVE and EXIT at top right. See p. 35, and choose the first item, Save and Exit, to save your settings and reboot.