This article covers ARCTIC Liquid Freezer III Pro 420 A-RGB (ホワイト).
Overview
The ARCTIC Liquid Freezer III Pro 420 A-RGB (White) is an all-in-one liquid CPU cooler built around a 420mm radiator with a 38mm thickness — a significant step up from the standard 27mm found on most AIOs. It targets enthusiasts who demand headroom for overclocking or sustained heavy workloads on high-TDP CPUs like Intel Core i9 or AMD Ryzen 9. The white variant includes three 140mm P14 Pro fans with addressable RGB lighting. The pump unit integrates a small VRM fan to actively cool the motherboard's voltage regulator area, a feature rare among AIO coolers. With native offset mounting for AMD AM5/AM4 and a contact frame for Intel LGA1851/LGA1700, it ensures optimal thermal transfer regardless of platform.
Connectivity & Compatibility
The cooler supports Intel LGA1851 and LGA1700 sockets (with included contact frame for uniform pressure), as well as AMD AM5 and AM4 with an offset mounting design that shifts the cold plate center toward the CPU's hotspot for more efficient heat transfer. All fan PWM cables are routed through the hose sleeve, leaving only one visible cable at the motherboard end — a thoughtful touch for cable management. The integrated VRM fan is PWM-controlled and requires a spare 4-pin header on the motherboard. The three P14 Pro fans also use standard 4-pin PWM connectors. Make sure your case can accommodate a 420mm (3x140mm) radiator; minimum case width and radiator support are critical.
Product Info
Released in the first half of 2025, the Liquid Freezer III Pro 420 A-RGB sits at the high end of the AIO cooler market. Its 38mm-thick radiator, combined with the integrated VRM fan and ARGB P14 Pro fans, places it in a tier where performance rivals custom-loop solutions while maintaining plug-and-play convenience. The price range is typically between ¥20,000 and ¥30,000 in Japan, reflecting its premium positioning. Accessories include three P14 Pro fans, mounting kits for Intel and AMD, a contact frame, thermal compound, and an ARGB controller adapter. For warranty details, check the official ARCTIC website.
Best Use Cases
High-end CPU owners seeking maximum cooling headroom: If you run an Intel Core i9-14900K or AMD Ryzen 9 7950X and plan to overclock or sustain heavy workloads (video rendering, 3D modeling), the 420mm+38mm combination provides exceptional thermal dissipation that keeps CPU temperatures under control even under prolonged stress. Enthusiasts with spacious cases: This cooler requires a case that natively supports a 420mm radiator — typically a full-tower or super-tower chassis. If you have the room, the white aesthetic matches white builds perfectly, and the integrated cable management keeps the build clean. * Users who want near-silent operation at idle: The P14 Pro fans excel at low speeds where they remain quiet, while the pump noise is also well-damped. On lighter loads, the system can run nearly inaudibly, and only ramps up under heavy loads.
