fan_minimum_pwm(9)

🎀 fan_minimum_pwm 🎀

okay so this is a section 9 kernel API manual page, bestie — fan_minimum_pwm(9), straight out of the Kernel API Manual. It's all about the amdgpu driver's sysfs API, and it's how you check and tweak the minimum fan speed in PWM. yes, the actual floor of how slow your fan is allowed to spin. iconic behavior honestly.

✨ what it actually does ✨

So the amdgpu driver ships a sysfs API for checking and adjusting the minimum fan speed in PWM. that's the whole vibe.

reading it back shows you the current setting, plus the permitted ranges — if it's changeable. lowkey the range info is the best part, don't skip it.

writing an integer to the file changes the setting accordingly. just an integer. that's it. slay.

when you're done editing, write "c" (commit) to the file to commit your changes. yes you have to commit, no it will not do it for you 😭

want the default back? write "r" (reset) to the file to reset them. one character, full undo, we love a reset arc.

okay important caveat time 🫶 this setting works under auto fan control mode only. it can co-exist with other settings which can work also under auto mode. it adjusts the PMFW's behavior about the minimum fan speed in PWM that the fan should spin. and heads up — setting via this interface will switch the fan control to auto mode implicitly. like, it just does that. no cap.

💅 SEE ALSO 💅

the kernel file itself lives at ./drivers/gpu/drm/amd/pm/amdgpu_pm.c — go read the source, it's giving main character energy:

• amdgpu_pm_dev_state_check(9)
• amdgpu_pm_get_access(9)
• amdgpu_pm_get_access_if_active(9)
• amdgpu_pm_put_access(9)
• power_dpm_state(9)
• power_dpm_force_performance_level(9)
• pp_table(9)
• pp_od_clk_voltage(9)
• pp_features(9)
• pp_dpm_sclk pp_dpm_mclk pp_dpm_socclk pp_dpm_fclk pp_dpm_dcefclk pp_dpm_pcie(9)
• pp_power_profile_mode(9)
• gpu_busy_percent(9)
• mem_busy_percent(9)
• vcn_busy_percent(9)
• pcie_bw(9)
• unique_id(9)
• thermal_throttling_logging(9)
• apu_thermal_cap(9)
• gpu_metrics(9)
• smartshift_apu_power(9)
• smartshift_dgpu_power(9)
• smartshift_bias(9)
• board(9)
• baseboard_temp(9)
• gpuboard_temp(9)
• cur_node_power_limit(9)
• node_power(9)
• npm_status(9)
• global_ppt_resid(9)
• max_node_power_limit(9)
• baseboard_power(9)
• baseboard_power_limit(9)
• pm_policy(9)
• hwmon(9)
• fan_curve(9)
• acoustic_limit_rpm_threshold(9)
• acoustic_target_rpm_threshold(9)
• fan_target_temperature(9)
• fan_zero_rpm_enable(9)
• fan_zero_rpm_stop_temperature(9)

okay that's the whole page, periodt 🌸 this little beauty came from the source tree at ./drivers/gpu/drm/amd/pm and it's dated October 2026 — so like, future-dated, timestamps are mysterious, we don't question it 💀 go forth and set your minimum PWM, bestie 💖✨🦋