Arctic S4028-15K Server Fan 40x40x28 Dual Ball - ACFAN00264A

Arctic S4028-15K is a small but aggressive 40 mm fan, primarily aimed at server and tightly packed cases, where airflow and pressure are more important than noise. The operating range of 1150–15000 RPM provides a lot of freedom – from relatively quiet mode to a true turbine when you need to blow out a serious amount of warm air. With a size of 40 x 40 x 28 mm and a 4-pin connector, it is a classic server fan that relies on PWM control. The dual bearing 2 Ball Bearing ensures a long life under 24/7 load, and the black design is simple and functional.

What you get

Here the focus is on pressure and reliability. With an airflow of 19.23 CFM and up to 26.5 mmH2O static pressure, the fan is suitable for dense radiators, narrow server chassis, and areas with very limited airflow. The 4-pin connector gives you PWM control – you can keep the fan at low speeds in idle and ramp it up to the upper limit when the component temperatures rise. The amperage of 0.47 A is important if you plan to use several such fans on one header – this way you can calculate the total load on the motherboard or controller. And with a warranty of 72 months, you have peace of mind for long-term use in a server or constantly loaded system.

• Compact size according to the 40 mm standard, allowing installation in server cases, networking devices, and narrow chassis.
• Actual size of 40 x 40 x 28 mm, providing slightly greater thickness for better static pressure compared to typical 10–20 mm fans.
• Range of 1150–15000 RPM, allowing you to balance between noise and maximum cooling according to the load.
• Airflow of 19.23 CFM combined with high pressure is suitable for blowing through dense radiators and restricted openings.
• Maximum static pressure of 26.5 mmH2O, aimed at scenarios where air needs to be “re-routed” through filters, radiators, or dense perforations.
• Reliable 2 Ball Bearing bearing, optimized for long life and operation in various orientations, including 24/7 server environments.
• 4 PIN PWM connector for precise speed control through the motherboard or fan controller, instead of operating only at fixed speeds.
• Black finish without RGB, suitable for professional and server configurations where functionality is paramount.
• Long 72 months warranty, which is a serious plus for components operating continuously under load.

Who it is suitable for

Arctic S4028-15K is a good choice if you are building a server, networking device, compact workstation, or a case with limited space where you need high pressure and reliability. It is also suitable for modifications of existing server systems where you want better control over the speeds. It is not the best option if you are looking for a quiet 120/140 mm fan for a standard gaming PC – this is more of a tool for specific, dense configurations.

The combination of very high maximum RPM, serious static pressure, and 2 Ball Bearing makes this 40 mm fan a stable choice for critical systems where cooling is more important than anything else.