1. The controller regulates the speed of standard four-wire Intel PWM fans only; it does not support fan shutdown. It features full digital control, precise temperature setting, and accurate speed regulation. It supports both manual speed adjustment and automatic temperature-based speed control. Manual speed adjustment ranges from 10% to 100%, in 5% increments. Automatic temperature-based speed control begins at 30°C, with 49 adjustable temperature zones. 2. Power input: Red and black wires connect to a 12V DC power supply. A three-wire connector with a 2510-3P plug is included for compatibility with motherboard three-wire fan headers for RPM monitoring. A large 4-pin interface enables convenient power connection from the chassis. 3. Temperature probe: The small black probe has a short tip and low thermal mass, enabling fast response for air or narrow-space temperature measurement. The ring-type probe is housed in a 4.2mm-diameter metal ring, suitable for mounting on heatsinks or other heat-emitting surfaces using screws. 4. Integrated manual/automatic control: Manual mode operates without the temperature probe. Press or double-press the up/down buttons to adjust speed. Each adjustment persists for 20 seconds before auto-saving. Indicator No. 2 flashes rapidly during the 20-second period when temperature control is inactive. Flashing stops once settings are saved. Indicators No. 3 and No. 1 remain steadily lit when maximum or minimum speed limits are reached. 5. With the temperature probe installed, the manually set speed serves as the base (minimum) speed. When ambient temperature exceeds the configured start temperature, fan speed increases smoothly with rising temperature. When temperature reaches or exceeds the sum of the start temperature and the temperature range width (i.e., the full-speed temperature threshold), the fan runs at maximum speed.