Fan Profiles & Control Logic

Pankha provides a sophisticated control engine designed to keep your system quiet when idle and cool when under load. This page explains how the control logic works.

Fan Profiles

A Fan Profile defines the relationship between a temperature source and a fan’s speed. Pankha ships with several built-in profiles, and you can create your own custom curves.

Built-in Profiles

Profile	Best For	Behavior
GPU Optimal	Graphics cards	Fans stay off when cool, kick in at 50°C, and reach full speed by 75°C.
Lazy	Chipset, high-RPM fans	Keeps fans completely off until 50°C, then slowly ramps up. Prioritizes silence over everything.
Optimal	General use	A good all-rounder. Fans spin gently at idle and ramp smoothly as temperatures climb.
Performance	Heavy workloads	Fans are always spinning (40%+) and ramp aggressively. Keeps things cool at the cost of noise.
Standard	Most systems	A straightforward linear curve from low to high. Predictable and reliable.
Raspberry Pi 5	SoC and ARM boards	Stays silent until 55°C, then ramps quickly. Tuned for small boards with high-RPM fans.

All built-in profiles can be used as-is or duplicated and adjusted to suit your hardware.

Control Logic

How does Pankha decide what speed to run a fan at?

Sensor Reading: Reads the Assigned Control Sensor (e.g., “CPU Package”).
Curve Lookup: Finds the target speed for that temperature on the active profile curve.
Hysteresis Check: Ignores small, rapid temperature fluctuations (see below).
Smoothing: Gradually adjusts the current speed to the new target (see “Fan Step”).

---
title: Fan Control Logic Pipeline
---
graph TD
    Sensor([Temperature Sensor]) -->|Reads 65°C| Logic{Control Engine}

    subgraph "Processing Pipeline"
        Logic -->|Lookup| Curve[Profile Curve]
        Curve -->|Target: 60%| Hysteresis{Hysteresis Check}

        Hysteresis -->|Unchanged| Current[Keep Current Speed]
        Hysteresis -->|Changed| Step[Smoothing Function]

        Step -->|Step +5%| PWM[Final Fan Speed]
    end

    PWM -->|Write| Fan([Physical Fan])

Assigning a Fan Profile

Each fan can be assigned:

A Fan Profile (the curve that determines speed behavior).
A Control Sensor (the temperature source that drives the curve).

Both are selected from dropdowns on each fan’s row in the dashboard.

Control Sensor Selection

When assigning a control sensor to a fan, you have three options:

Individual Sensor

Select a specific sensor (e.g., “CPU Package”, “GPU Core”). The fan speed is based entirely on that single sensor’s temperature.

Highest Temperature

Select “Highest” to use the maximum temperature across all visible sensors on that system. This is ideal for exhaust or case fans that should respond to whatever is hottest.

Only visible sensors are included. If you hide a sensor (see Advanced Settings), it is excluded from the highest calculation.
This lets you declutter noisy or irrelevant sensors without affecting your fan behavior, or intentionally exclude sensors you don’t want driving your fans.

Sensor Group

Select a sensor group (e.g., “k10temp”, “nvme”) to use the highest temperature within that group only. Useful when you want a fan to respond to a specific hardware component:

Group Example	Sensors Included	Use Case
`k10temp`	All CPU core sensors (AMD)	CPU fans
`coretemp`	All CPU core sensors (Intel)	CPU fans
`nvme`	All NVMe drive temperatures	Drive bay fans
`it8628`	All motherboard chip sensors	Case fans

Groups are based on the hardware chip name reported by your system. The available groups will vary depending on your hardware.

Custom Fan Curves

When using the Custom profile type, you define your own temperature-to-speed curve with as many control points as you need.

Open the Fan Profile Manager from the fan’s profile dropdown.
Add or edit control points on the curve graph.
Each point maps a temperature (X-axis) to a fan speed percentage (Y-axis).
The fan speed is linearly interpolated between points.

Example custom curve:

Temperature	Fan Speed
30°C	20%
50°C	40%
65°C	70%
80°C	100%

At 57°C, the fan would run at approximately 55% (interpolated between the 50°C and 65°C points).

Bulk Edit

If you have many fans on a system, you can update multiple fans at once using the Bulk Edit panel.

Click the Bulk Edit button on a system card.
Select the fans you want to change (or use Select All).
Choose a Fan Profile and/or Control Sensor to apply.
The selected settings are applied to all checked fans in one action.

This is especially useful when setting up a new system for the first time, or when changing the profile for all case fans at once.

Advanced Settings: Hysteresis, Fan Step, Emergency Temperature, and Sensor Visibility settings that affect fan control.
Troubleshooting: Fan control not working or fans not responding.