Computer Systems Servicing

Faults, Reporting, and Procedures

Learning Competencies

1.1

Obtain work instruction in accordance with standard operating procedures.

1.2

Check received materials

Against workplace standards and specifications (Factory Defects & Nonconformity).

1.3

Identify and isolate faulty materials

Related to work (Safety Defects & Isolation).

1.4

Record and report defects

Identify causes to supervisor in accordance with workplace procedures.

1.5

Replace faulty materials in accordance with workplace procedures.

1. Factory Defects

Faults that occur during the manufacturing process before the product reaches the consumer.

Dead on Arrival (DOA) components.
Solder bridges or "cold" joints.
Physical damage within packaging.

Factory Defects & DOA

A flaw resulting from a mistake during creation or assembly, rather than user error.

Real-World Scenarios:

Dead on Arrival (DOA): A brand new PC won't POST because the CPU socket has bent pins straight out of the box.
Cold Solder Joints: A GPU crashes after 10 minutes due to poor soldering losing contact when warm.

Close-up of a computer processor (CPU) with bent and damaged pins

Why does this happen?

Mass production stress, environmental fluctuations (humidity in cleanroom), or "Silicon Lottery" batch errors.

Solder Bridges & Cold Joints

Common physical defects on PCBs like motherboards.

Solder Bridge

Unintended connection between two pads causing a short circuit.

Cold Solder Joint

Solder didn't melt completely; creates high resistance/intermittent connection.

Physical Damage (Sealed)

"Concealed Damage" - Broken components despite intact retail box seals.

Examples:

Cracked screens inside foam padding.
Heavy GPU heatsinks snapping off due to inertia drops.

2. Nonconformity to Specifications

When hardware fails to meet the performance or physical requirements promised in the technical data sheet.

RAM clocked lower than advertised speeds.
Power Supply Units (PSU) providing unstable voltages.
Incompatible dimensions for rack-mount installations.

RAM Speed Mismatch

Installed memory runs at "Safe Default" (e.g., 2133MHz) instead of advertised speed (e.g., 3200MHz).

Advertised: DDR4-3200 Actual: DDR4-2133

Fix: Enable XMP/DOCP in BIOS. If it crashes, the RAM is defective.

PSU Instability

PSU fails to deliver steady voltage within ATX Tolerance (±5%).

Rail	Fail Condition
+12V	< 11.40 V
+5V	< 4.75 V

⚠️

Unstable voltage creates "Ripple" which kills HDDs and CPUs over time.

⚠️ 200mm Overhang!

Dimensional Mismatch

Hardware meets electrical specs but fails physical installation (Rack Depth).

The "Depth" Trap

Installing a deep Server (800mm) into a shallow Network Cabinet (600mm).

3. Standards & PEC Compliance

Compliance with the Philippine Electrical Code (PEC) and environmental laws ensures longevity and legality.

PEC & Environmental

Proper grounding, wire gauging (Ampacity), and E-waste disposal (WEEE).

Safety Defects

Exposed wiring, lack of surge protection, or fire hazards.

Grounding & Gauging

1. Equipment Grounding

PEC mandates a 3-wire system. Removing the ground pin ("Cheater Plug") leaves the PC case floating, causing shocks.

2. Wire Gauging (AWG)

Using thin wires (high AWG) for servers causes overheating and melting.

Violation:

Breaking the 3rd pin violates PEC Art. 2.50. PEC Article 2.50 refers to the section of the Philippine Electrical Code (PEC) titled "Grounding and Bonding."

Safety: Fire & Shock

Exposed Wiring

Insulation stripped by rodents or pinch points.

"Octopus" Connection

Daisy-chaining extension cords exceeds amperage rating.

Fire Hazard

Reporting Procedures

Parts Identification

Identifying sub-assemblies (HDD, PSU, GPU) by Serial Numbers and Model Types.

Component ID

Granular tracking of capacitors, ICs, or connectors within a specific part.

Parts: Model vs Serial

Model Number (The "Type")

Used for compatibility/drivers. (e.g., "Samsung 970 EVO")

Serial Number (The "ID")

Unique to that unit. Used for Warranty/Theft recovery.

Model

S/N

C962

Component Level ID

Identifying the specific electronic element (C=Capacitor, R=Resistor, U=IC) causing failure.

The Benefit

Allows for "Board Level Repair" (₱200 fix) instead of "Board Replacement" (₱10,000 cost).