Conflict with Gigabyte motherboard

[zRafaX]

Description

When I close Fan Control (even using the Exit option from the system tray) or restart/shut down my PC with Fan Control running, my fans (CPU and System) go to 100% RPM and stay there until I manually reset the BIOS (Clear CMOS). This happens even if I have a custom fan curve configured in the BIOS as a fallback.

The issue occurs every time I close Fan Control or restart/shut down, regardless of how I close it. The only way to restore normal fan behavior is to enter the BIOS, load optimized defaults, or Clear CMOS.

• Motherboard: Gigabyte B760M D2H DDR4 (Rev. 1.0)

Steps to Reproduce

1. Open Fan Control and apply custom curves to CPU and System fans.
2. Close Fan Control using any method (click the X button, use Exit from the system tray, or shut down/restart the PC).
3. Turn the PC back on.
4. Observe that the CPU and System fans are spinning at 100% RPM and ignore the BIOS fan curve.
5. The only way to fix this is to enter the BIOS, load optimized defaults, or Clear CMOS.

Temporary Workaround

• Clear CMOS or Load Optimized Defaults in BIOS to restore normal fan behavior.
• After that, the only way to keep fans working properly is to not use Fan Control at all for CPU and System fans, or never close it.

Additional Notes

I noticed that this issue only happens with Gigabyte motherboards. I've seen similar reports in issues #3781, #3633, #1751, and #1465. It seems like the EC (Embedded Controller) on Gigabyte boards doesn't properly handle the control handoff when Fan Control is closed.

[Rem0o]

Kind of a known issue, but I have no clue how to address it. The handoff routine on close looks ok. The main problem is that all work done the Gigabyte EC is reverse-engineered from GCC, not actually done with proper documentation (as it isn't made available/public).

[CgZ1177]

Similar problem on a GIGABYTE b550m-ds3h motherboard, but for me it doesn't happen every time I close Fan Control, only sometimes. I just need to restart the computer normally for the CPU fan to respond again (maybe some custom setting in my BIOS differs from yours). I still haven't managed to figure out the logic behind the failure.