Computer Cooling Methods Overview

Jun 7, 2025

Overview

This lecture covers computer cooling methods, including airflow, fans, heat sinks, thermal paste, thermal pads, passive cooling, and liquid cooling systems.

Airflow and Fans

  • Computer components generate heat, requiring efficient cooling for system stability.
  • Fans are used to pull cool air through one side of the case and expel hot air from the other.
  • Proper layout and cable management improve airflow across components.
  • Fans come in standard sizes (e.g., 80 mm, 120 mm, 200 mm) and often have variable speeds.
  • High-performance adapter cards (e.g., graphics cards) may have dedicated fans.
  • Faster fans increase noise; different models have varied noise levels.

Passive Cooling

  • Passive cooling systems use no fans, relying instead on heat dissipation through heat sinks.
  • Passive cooling is favored in quiet environments and low-heat devices (e.g., video servers, set-top boxes).

Heat Sinks

  • Heat sinks spread heat from a component over a larger area using metal fins.
  • Airflow over heat sink fins transfers heat from the fins to the air.
  • Heat sinks can become very hot; caution is needed during handling.

Thermal Paste and Pads

  • Thermal paste (thermal grease) is applied between a hot component and heat sink to ensure optimal heat transfer.
  • Only a small amount of thermal paste is needed between the component and heat sink.
  • Thermal pads are an alternative to paste, simpler but less effective, and must be replaced if removed.
  • Both thermal paste and pads are not reusable.

Liquid Cooling Systems

  • Liquid cooling is used for high-end or overclocked systems needing advanced heat removal.
  • Liquid cooling includes a heat sink on the CPU, coolant pipes, a radiator, and fans.
  • Coolant absorbs heat from the CPU, flows to the radiator to dissipate heat, and returns to the CPU.

Key Terms & Definitions

  • Airflow — Movement of air through the computer case to cool components.
  • Heat sink — Device that dissipates heat from components using metal fins.
  • Thermal paste/grease — Conductive substance that improves heat transfer between components and heat sinks.
  • Thermal pad — Solid pad placed between components and heat sinks for thermal transfer.
  • Passive cooling — Cooling method using no moving parts, relying on heat sinks.
  • Liquid cooling — System using liquid coolant to transfer heat away from components.

Action Items / Next Steps

  • Ensure cables and components are arranged to maximize airflow in your system.
  • Use the proper amount of thermal paste or a fresh thermal pad when installing or replacing heat sinks.
  • Research the different fan and cooling options suitable for your computer's noise and performance needs.