ARCTIC Liquid Freezer III 420 A-RGB Black with 420mm radiator, triple 140mm A-RGB fans, VRM fan, PWM pump and Intel/AMD compatibility.

Push your gaming or workstation PC to higher sustained performance with the ARCTIC Liquid Freezer III 420 A-RGB Black, a premium 420mm all-in-one CPU liquid cooler engineered for demanding processors and high-performance desktop builds. It combines a large aluminum radiator, a copper micro-skived cold plate, a PWM-controlled pump, three 140mm P14 PWM PST A-RGB fans, and a dedicated VRM fan to deliver comprehensive cooling around the CPU socket. 

The cooler uses a 458 × 138 × 38mm radiator and 450mm tubing, giving the system a substantial cooling surface for removing heat from high-load CPUs. The pump operates from 800 to 2800 RPM, while the three P14 fans run from 200 to 1900 RPM, providing up to 69.90 CFM airflow per fan. The integrated VRM fan operates independently from 400 to 2500 RPM, helping direct airflow around the motherboard's voltage-regulation components.

The Liquid Freezer III 420 A-RGB also adds 12 A-RGB LEDs per radiator fan plus 12 LEDs on the VRM fan module, with a 5V 3-pin A-RGB connector for compatible lighting systems. ARCTIC includes MX-6 thermal compound, and the current black version carries a 6-year manufacturer warranty.

KEY FEATURES

• 420mm AIO CPU Liquid Cooler – Large radiator designed for demanding gaming and workstation processors.
• Triple 140mm P14 PWM PST A-RGB Fans – Three high-airflow fans mounted to the radiator for efficient heat dissipation.
• 800–2800 RPM PWM Pump – Adjustable pump speed for responsive cooling control.
• 200–1900 RPM Fan Range – PWM-controlled radiator fans balance cooling performance and acoustics.
• Up to 69.90 CFM Airflow per Fan – High airflow through the radiator for effective heat removal.
• Copper Micro-Skived Cold Plate – Enlarged micro-fin structure is designed to improve heat transfer from the CPU. 
• Dedicated VRM Cooling Fan – The integrated 400–2500 RPM fan directs airflow around the CPU socket and VRM area.
• 38mm-Thick Aluminum Radiator – Large radiator structure increases cooling surface and thermal capacity.
• 450mm Tubing – Provides flexibility when positioning the radiator inside larger PC cases.
• 5V 3-Pin A-RGB Lighting – Connects to compatible motherboard ARGB headers for synchronized illumination.
• Pre-Installed Radiator Fans – The cooler arrives with the radiator fans already installed for easier setup. 
• MX-6 Thermal Compound Included – Ready to install without requiring separate thermal paste.
• Single-Cable Motherboard Connection – ARCTIC integrates the fan cables into the tubing sleeve for a cleaner installation.

Advanced Cooling Design 

The Liquid Freezer III 420 A-RGB is built for high thermal loads. Its large 420mm radiator works with three 140mm fans, while the copper cold plate uses micro-skived fins to increase the effective heat-transfer structure above the CPU. The integrated VRM fan provides additional airflow around the CPU socket rather than cooling only the radiator.