Liquid Cooling Glossary

This list contains the most important abbreviation, portmanteaus and other important lingo, used in the computer liquid cooling community:

    • ABS: Acrylonitrile butadiene styrene, a common and popular mould injection material for in the liquid cooling industry.
    • ACF: EK's Advanced Compression Fitting. Comes in many varieties and doesn't need any clamps to secure the tubing.
    • Acrylic: Polymethyl methacrylate (PMMA). See Plexi.
    • Air Flow: Air flow is a movement of air, usually generated by any form of fan. The higher the airflow, the better the performance.
    • Air Flow Fan: See Case Fan.
    • Bow: Refers to the curvature of the contact surface of water blocks (usually in reference to CPU blocks). The bow angle and type (concave/convex) can be changed depending on the application and is intentionally designed as such.
    • Block: Water block or cold head/plate is the part of the liquid cooling loop which draws the heat from the PC components.
    • Bridge: Usually a term, associted with connecting multiple graphics cards water blocks (i.e. Full Cover) together with a single manifold. EK uses two different types. See FC FC Bridge CSQ and FC Terminal.
    • Case Fan: A cooling fan, intended for ventilation of PC chassis. Built for high air flow but does not generate much static pressure. Not recommended for radiator cooling.
    • Chipset: A term to denote motherboard's main logic, originally consisting of South Bridge and North Bridge. On most modern motherboards North Bridge is integrated into CPU. See NB, SB.
    • CNC: Computerized Numeric Control; usually stands for CNC mills, the main machining tool of the trade by which products are made.
    • Combo (Unit): A combined unit with pump and reservoir within the same assembly. Sometimes called "pump/res combo".
    • Coolant: Cooling liquid; a mixture of corrosion / algae inhibiting chemicals and distilled water for use in PC liquid cooling.
    • Conductivity: A term denoting electrical conductivity of the liquid cooling medium (coolant). Coolants have very low electrical conductivity.
    • Corrosion: The process of gradual destruction of (dissimilar) metals by chemical reaction with their environment. Can be effectively inhibited using coolants.
    • CPU: Central Processing Unit; the main microprocessor of the computer.
    • CSQ: The Circle SQuare design by EK, introduced in summer of 2012. Radical, stirred a lot of hell but still loved by many. Full Cover CSQ blocks (now called Original CSQ) use EK-FC Bridge CSQ system. Modders love to polish these!
    • D5: A renowned cylindrical high flow liquid cooling pump from Laing/Xylem. Quiet and powerful.
    • DBAY: A dual 5.25" drive bay slot occupying reservoir or pump/reservoir combo unit.
    • DDC: A renowned square-shaped tiny, yet very powerful high pressure liquid cooling pump from Laing/Xylem.
    • Delid / De-lid: A process of removing microprocessor's integrated heat spreader (IHS) in order to obtain better cooling performance by improving the heat transfer. See My CPU is overheating!
    • Delrin: Commercial trade name for POM. See Acetal.
    • Delta / Delta T: The difference between two temperature readouts; usually stands for temperature difference between ambient- and liquid (water) temperature. The lower the delta, the better the cooling system.
    • EK-CEO: The Boss, much like Bruce Springsteen. Overly-enthusiastic about his new forum role. Soon to be regretting it.
    • EPDM: A type of high quality industrial grade rubber, used in EK ZMT tubing. See ZMT.
    • Fan Bearing: A machine element that constrains relative motion to only the desired motion, and reduces friction between moving parts. Ball bearing is more audible in operation than sleeve bearing but much more durable and reliable.
    • Fill Port: Optional loop component for easier filling and emptying of the liquid cooling system. Personal taste.
    • Flux: Pre-soldering surface treatment/cleaning agent, usually found present in radiators.
    • Full Board: A motherboard water block (kit) that cools all vital parts - VRM, SB/PCH and also NB if present.
    • Full Copper / Full Nickel: A term used by EK to describe a water block, which is completely made of copper and copper alloys. Usually flagship performance CPU block.
    • Full Cover: A graphics card water block that cools GPU, RAM IC and also VRM. There are also variants that only cool GPU and RAM IC.
    • Glycol (ethylene and propylene): Corrosion inhibiting additives found in coolants. Also very effective against algae growth. Ethylene gycol by itself is very toxic and is mixed with detox additives in modern coolants.
    • Goofy (orientation): A term invented by the community to describe the rotated (90° clock-wise) installation orientation of the CPU water block.
    • GPU: Graphics processing unit - the graphics card processor. Also common (but incorrect) use as a description of complete graphics / video card.
    • Gunk: An unknown thick build up in liquid cooling loop, consisting of debris, insoluble chemicals and/or organic growth.
    • HFB: EK's High Flow Barbs fitting. Comes in many variants, requires hose clamp or adequate substitute for safest operation.
    • IHS: Integrated Heat Spreader; usually a plated copper cover plate which protects microprocessors from (spot) overheating. Can be soldered or glued to microprocessor.
    • Insert: Part of Supremacy EVO/MX CPU water block internal flow streamer. There are different inserts, optimized for different CPU platforms.
    • IX: Indigo Xtreme, a renowned phase change alloy TIM.
    • Jet (Plate): A nozzle within a water block which increases the liquid flow velocity in order to further aid cooling performance.
    • Loop: Short for liquid cooling loop / circuit, which consists of water block, radiator (with fan), pump and reservoir.
    • Monoblock: A motherboard all-in-one water block, which cools CPU, VRM as well as PCH (SB). Requires very little effort to get it running in comparision to traditional multi-block arrangement.
    • Mounting plate: A hold-down plate, specific for each CPU socket or GPU hole spacing pattern. Exchangeable mounting plates allow the same water block to fit many platforms.
    • Mosfet: A field-emiting transistor, crucial part of VRM. Also stands for motherboard VRM water blocks (i.e. "a mosfet block").
    • NB: North Bridge is a part of motherboard's chipset, which consists of NB and SB. Modern motherboards do not have NB (as NB is integrated into CPU) but rather a PCH.
    • Neoprene: High quality industrial grade synthetic CR rubber. Rarely used for tubing.
    • Nickel (plating): A fine, thin layer of electrolitically deposited nickel on the bare copper base. Improves the look and prevents copper tarnishing.
    • Norprene: High quality industrial grade synthetic rubber. A notch better chemical resistance than EPDM but very expensive.
    • Oxidation: Naturally occuring reaction between metal and oxygen in the presence of water or air moisture. Practically impossible to prevent. Not the same as corrosion.
    • Parallel: Describes the liquid flow distribution. In parallel connection every liquid cooling block receives only a portion of the total flow rate. Not recommended for blocks with dissimiliar pressure drop characteristics. Large parallel flow loops may result in a low partial flow rates through water blocks.
    • PCH: Platform Controller Hub is a motherboard's chipset. Intel's term. Also known as SB.
    • Plug: A threaded plug for closing of unused ports on the liquid cooling gear.
    • POM: Polyoxymethylene. See Acetal.
    • Pressure (head): The maximum pumping height of a liquid cooling pump with no flow at all, not achievable under normal circumstances. The higher the value, the more suitable is the pump for big liquid cooling loop with water blocks in serial connection.
    • Pressure drop: The hydraulic pressure difference seen between the input and output of a cooling component. The higher the flow rates, the higher the pressure drop. Pressure drop is a function of restriction, which is due to differences in general construction.
    • PETG: Polyethylene terephthalate glycol. Plastic material, a popular choice for hard (solid) tubing, an alternative to Acrylic.
    • PVC: Polyvinyl chloride, with addition of plasticizers a popular material for soft translucent tubing. See Plasticizer and Tubing.
    • PWM: Pulse-Width Modulation, modern duty cycle control allowing fans and pumps to perform on demand. Unlike voltage control PWM control actually lowers power draw.
    • Rad: Short for liquid cooling radiator.
    • Rad(iator) Fan: A cooling fan, intended for cooling of radiators (i.e. Vardar). Also known as High Static Pressure Fan. Generates high static pressure but produces less air flow. Not ideal for chassis ventilation (see Case Fan).
    • Res: Short for reservoir.
    • RAM IC: Memory chips, may be either on the graphics cards or standalone memory modules.
    • QDC: Quick DisConnect fitting; allows disconnecting parts of the loop for replacement or maintenance without draining the coolant.
    • SB: South Bridge is a part of motherboard's chipset, which consists of NB and SB. SB portion carries USB, SATA and other periphery controllers. See PCH.
    • SBAY: A single 5.25" drive bay slot occupying reservoir or pump/reservoir combo unit.
    • Serial: Describes the liquid flow distribution. In serial connection every liquid cooling block has the same flow rate. Large serial flow loops may result in a big pressure drop.
    • Soon™: A term EK uses to re-assure its customers about overdue release dates.
    • Standoff: A metallic threaded spacer used to prevent over tightening and subsequent damage to the computer hardware, mostly motherboards and graphics cards.
    • Static Pressure: Pressure generated by the cooling fan at zero flow conditions. Liquid cooling radiators operate best when combined with high static pressure fans.
    • Static Pressure Fan: See Rad(iator) Fan.
    • Tarnishing: A term usually associated with copper and brass surfaces changing hue and turning dark. See Oxidation.
    • Temp(s): Short for temperature (i.e. "what are your temps?")
    • tiborrr: A vocal fellow who dislikes stupid questions before he sips his morning dose of coffee.
    • TIM: Thermal interface material or thermal grease. Used to improve thermal contact between water blocks and microprocessors.
    • Tubing: The hose through which the cooling medium (coolant) is transferred from one liquid cooling loop component to another. Comes in many sizes, colors and materials. See PVC and EPDM.
    • VRM: Voltage Regulation Module is a power delivery system of a computer component. Usually requires active cooling, especially on the modern high power graphics cards. See Mosfet.
    • XRES: EK improved volute liquid cooling pump with integrated reservoir. A combo unit (Pump + Res) for less hassle.
    • XTOP: EK improved volute liquid cooling pump. Comes with functionally improved housing and mounting. More performance and easier handling than factory pumps.
    • ZMT: EPDM matte black industrial grade tubing which contains no plasticizer. Zero Maintenance Tubing. See EPDM and Plasticizer.
Have more questions? Submit a request


  • 1
    Leo Aggebrandt
    • tiborrr: A vocal fellow who dislikes stupid questions before he sips his morning dose of coffee.


Article is closed for comments.
Powered by Zendesk