Noctua NF-A4X20 5V PWM Computer Cooling System

The total volume of air that a product can move, expressed in cubic meters per hour (m³/h) or cubic feet per minute (CFM). It indicates the overall ventilation capacity and is useful for comparing cooling performance across fans, heat sinks, and HVAC units.

The classification of the mechanical bearing used in a product, such as ball, sleeve, fluid dynamic, hydraulic, magnetic levitation or other specialized types. It indicates the internal design that determines load capacity, noise level and durability.

The linear distance that a cable covers, expressed with a length unit such as meters, centimeters or inches. It represents the total usable length of the cable for connecting devices.

A brief statement indicating the edition or version of a product, such as "Reprint", "New Edition", or a numeric edition number like "2nd edition". It identifies which specific release of the item is being referenced.

The colour or combination of colours that a fan is available in, expressed as common names such as "Black", "White" or comma‑separated lists like "Black, White". It indicates the visual appearance of the fan for consumers.

The linear measurement of a fan from front to back or top to bottom, expressed in a physical unit such as millimeters, centimeters, inches, etc. It indicates how deep the fan is and can be used for fitting, compatibility, or spatial planning.

Specifies the primary performance focus of a fan, such as airflow, static pressure, or quiet operation. It helps users choose a fan that best matches their cooling needs.

The rotational speed of a fan expressed in revolutions per minute (RPM). This value indicates how fast the fan blades turn, which affects airflow and cooling performance for the component it serves.

A list of the operational states that an LED indicator on a device can display, such as power status, activity, link, or other functional signals. Each entry represents a distinct status that the LED may show when the device is in use.

Indicates whether the product allows manual adjustment of its operating speed, such as a fan or motor that can be set to different RPM levels by the user.

Indicates whether the product includes Pulse‑Width Modulation (PWM) control for fan speed or other components, allowing variable speed adjustment via a controller.

The intensity of sound produced by a product, expressed in decibels (dB) or sones. It indicates how loud the device is during operation and helps users assess suitability for quiet environments.