Topic: Power Delivery, PSUs, Adapters, Battery Behavior, and Electrical Faults

❓ Essential Question

How does proper power delivery impact computer stability, and how can technicians identify and diagnose electrical faults in real systems?

⭐ Key Ideas

• Power issues look like “random problems” — but they follow patterns.
• Every system converts AC → DC before components can use it.
• PSUs, adapters, and batteries have specific voltage and amperage requirements.
• Faulty power is the root cause of many intermittent failures.
• Technicians must recognize symptoms instantly.

🔑 Vocabulary

PSU (Power Supply Unit) — Converts AC wall power to multiple DC rails.

Rail — A specific DC voltage output (+12V, +5V, +3.3V).

Wattage — Total power capacity (Voltage × Current).

Amperage (A) — The amount of current supplied.

Voltage Drop — When voltage falls below required levels.

Overcurrent Protection (OCP) — PSU safety system that shuts down when drawn too hard.

DC Barrel Adapter — Charger used by Chromebooks/laptops.