After upgrading the Razer Blade 18 (2025) to BIOS 2.00, the fan speed control in Razer Synapse is behaving abnormally.
In Razer Synapse, whether in Balanced Mode or Silent Mode (with fan control set to Auto), the system's fans can only operate at a minimum speed of 1500–1600 RPM or higher during low load or idle. Occasionally, switching between Balanced and Quiet modes causes the fans to turn off for a few dozen seconds, but once the temperature rises slightly, they return to 1500–1600 RPM.
Additionally, Manual Fan Curve settings cannot reduce the speed below 1600 RPM. While the System Monitoring display shows the adjusted speed when set below 1600 RPM, the actual fan noise confirms that the speed does not decrease. However, setting a speed above 1600 RPM allows the fans to be controlled normally.
In summary, the fans now cannot operate below 1600 RPM unless they are completely turned off.
Device: Razer Blade 18 2025(RZ09-0529)
System: Windows 11 Home 24H2 26100.4351(Razer OEM official system)
Razer Synapse: 4.0.86.2506190916
Bios: 2.00, 5/13/2025
Thanks for reading

