PSU Connectors & Types for A+
Short answer
The 20+4 pin connector is the standard main power cable from a PSU to motherboard; it supplies multiple DC rails. Modular PSUs let technicians attach only the cables needed, simplifying builds and reducing clutter. Redundant PSUs provide a backup power path so that if one PSU fails, the other continues powering the system-a high-availability feature rather than a performance-boosting one.
Why it appears on the exam
- Identify the 20+4 main connector in a photo. - Decide whether a modular PSU is helpful for a compact build scenario. - Given a scenario demanding high uptime, select redundant PSUs as the correct rationale.
Key concepts
Concept 1
Required terms
20+4 pin motherboard connector: The primary ATX main power connector that attaches the PSU to the motherboard; '20+4' indicates a 20-pin base plus a detachable 4-pin to support newer boards. modular power supply: A PSU design where some or all cables are detachable, allowing only needed cables to be connected for better cable management. redundant power supply: A design (often used in servers/workstations) where two or more PSUs provide power such that failure of one unit does not remove power from the system, improving uptime.
Example
Replacing a PSU in a small office PC: a modular PSU simplifies cable routing but is not required for function.
Concept 2
How PSU Connectors & Types works
The 20+4 pin connector is the standard main power cable from a PSU to motherboard; it supplies multiple DC rails. Modular PSUs let technicians attach only the cables needed, simplifying builds and reducing clutter. Redundant PSUs provide a backup power path so that if one PSU fails, the other continues powering the system-a high-availability feature rather than a performance-boosting one.
Example
In a server chassis labeled 'redundant PSU', two hot-swap modules provide continuous operation if one fails.
Concept 3
Common confusion
- Confusing connector shapes: the 20+4 main connector is large; the CPU 4/8-pin connectors are separate and smaller. - Assuming modular PSUs are inherently higher quality; modularity is about cable routing, not necessarily electrical specs. - Assuming redundant PSUs increase peak available power; they are primarily for redundancy and continuous uptime.
Example
Distinguishing the 20+4 main connector from a 4-pin CPU power connector during installation to avoid mis-plugging.
Concept 4
Core 1 (220-1201) question cues
Identify the 20+4 main connector in a photo; Decide whether a modular PSU is helpful for a compact build scenario; Given a scenario demanding high uptime, select redundant PSUs as the correct rationale.
Example
Replacing a PSU in a small office PC: a modular PSU simplifies cable routing but is not required for function.
Sample questions
Select an answer to reveal the explanation. For tracked practice and review of what you missed, use the Cultiv8 app.
Q1.In an A+ question, this detail appears: Replacing a PSU in a small office PC: a modular PSU simplifies cable routing but is not required for function. Which option matches it?
Q2.A support ticket includes this clue: In a server chassis labeled 'redundant PSU', two hot-swap modules provide continuous operation if one fails. Which concept is being tested?
Q3.An A+ support scenario describes this situation: Distinguishing the 20+4 main connector from a 4-pin CPU power connector during installation to avoid mis-plugging. Which answer fits best?
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