FLASH CARDS

1.07 Install or replace the appropriate power supply

  • Power Supply Unit (PSU)

  • Converts alternating current (AC) from an electrical outlet to low voltage direct current (DC) power for PC components, ensuring safe and efficient operation.

  • Conversion

  • The process by which a PSU changes AC to DC voltage using a rectifier, transformers, and filters.

  • Cooling (PSU)

  • A fan within the PSU dissipates heat generated during the conversion process to prevent overheating.

  • Compatibility (PSU)

  • The PSU must match the size, shape, and form factor of the system case and motherboard, typically following the ATX standard for desktop PCs.

  • Input Voltage

  • The voltage that a PSU requires from an electrical outlet. Most PSUs are dual voltage (100-127 VAC for low-line and 220-240 VAC for high-line) and auto-switching.

  • Regional Differences

  • PSUs designed for North America (120 VAC) may not work in regions like the UK (230 VAC) unless they are dual voltage or have a manual switch.

  • Wattage Rating

  • Indicates the capacity of a PSU to meet the combined power requirements of a computer's components, measured in watts (W).

  • Efficiency (PSU)

  • The ratio of the PSU's output power to its input power. Higher efficiency means less power loss as heat. ENERGY STAR 80 PLUS compliant PSUs must be at least 80% efficient from 20% to 100% load.

  • Power Distribution (PSU)

  • PSUs provide different output voltages across various rails (e.g., +3.3V, +5V, +12V), each supplying power to different components.

  • Rail (PSU)

  • An electrical circuit within a PSU that delivers a specific voltage level to components. Common rails include +3.3V, +5V, and +12V.

  • Maximum Load

  • The maximum amount of electrical current in amperes (A) that a rail can safely provide without causing damage or instability.

  • Maximum Output

  • The highest power in watts (W) a rail can deliver, calculated by multiplying the rail's voltage by its maximum load (current).

  • P1 Connector

  • The main power connector for the motherboard, originally a 20-pin in the ATX specification, now usually a 24-pin in the ATX12V version 2 specification.

  • Modular PSU

  • A PSU with detachable cables, reducing clutter inside the PC case and improving airflow and cooling.

  • Redundant PSU

  • A setup with two PSUs in servers, where one acts as a backup. If one fails, the other takes over without losing power.