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AIO (all-in-one) cooler

A sealed, pre-filled liquid CPU cooler that ships as one ready-to-install unit, sized by its radiator.

AIO (all-in-one) cooler A sealed liquid loop joins a pump-block on the CPU to a fan-mounted radiator by pre-filled tubing; sizes are named for the fans, like 360mm. CPU socket Pump + block Radiator 3 fans = 360mm Sealed, pre-filled tubing One closed unit, no maintenance Buying check: case must support this radiator size

A sealed, pre-filled liquid CPU cooler that ships as one closed unit — pump, tubing, fans and radiator already assembled — so it installs more like an air cooler than a custom water loop and needs no maintenance. The radiator comes in sizes named for the fans it holds, commonly 240mm, 280mm and 360mm, and a bigger radiator generally cools better and can run quieter at a given temperature.

Concrete example

a 360mm AIO needs a case with a 360mm radiator mount, often in the top or front.

What it means when you're buying

the make-or-break check is whether your case officially supports the radiator size and mounting position you're buying — measure or read the case spec first — and verify the cooler includes a bracket for your CPU socket.

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