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 weak-area review, 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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