Water block

A water block is the liquid-cooling counterpart to a standard heatsink, operating as a plate heat exchanger. It can be applied to various computer parts, such as the CPU, GPU, PPU, and the motherboard's northbridge chipset. There are also monoblocks designed to mount directly on the motherboard, covering both the CPU and the surrounding VRMs (Voltage Regulator Modules) that handle power delivery. The block is built from at least two main components: a base that makes direct contact with the component being cooled, typically made from highly conductive metals like copper or aluminum, and a top that seals the water inside and features inlet and outlet connectors for tubing. The top can be crafted from the same metal, or from materials like transparent Perspex, Delrin, Nylon, or HDPE. Many modern high-end water blocks also incorporate mid-plates, which house jet tubes, nozzles, and other devices that alter water flow.

The base, top, and any mid-plates are sealed together to create a block with an internal path for water. The ends of this path have connectors for the tubing that links the block to the rest of the cooling loop. Early designs used spiral, zig-zag, or fin-like patterns to maximize surface area for heat transfer, based on the assumption that high flow rates were key to performance. However, trial and error in water block evolution revealed that trading some flow for increased turbulence often boosts performance. The Storm series of water blocks exemplifies this: its jet tube mid-plate and cupped base restrict water flow more than early maze designs, but the resulting turbulence yields a significant performance gain. Newer designs include pin-style blocks, jet cup blocks, refined maze patterns, micro-fin structures, and variations on these ideas. These increasingly restrictive designs have become possible only because commercially available water pumps now offer higher maximum head pressure.

A water block dissipates heat more effectively than an air-cooled heatsink, thanks to water's higher specific heat capacity and thermal conductivity. The water is pumped to a radiator, where a fan pushes air through it to expel the heat into the environment. A radiator is more efficient than a standard CPU or GPU air cooler because it provides a much larger surface area for heat exchange.