Part A: Support
Systems support and integration
Key takeaways
- A support technician groups a computer's electronic components into four: the system unit, secondary storage, input/output devices and communication devices, each with its own faults and handling rules.
- The six maintenance tools are simple hand tools, diagnostics software, a multimeter, chemicals with freeze sprays and compressed air, foam or lint-free swabs, and a memory module tester.
- Diagnostics software is the first tool to reach for, because it narrows the fault before any hardware is touched.
- A measurement justifies a part: ATX supplies hold each rail within 5% of nominal, so a +12 V line that drops to 10.6 V under load is failing.
- The greatest risk during disassembly is the static charge on the technician, so mains power is disconnected first and an anti-static strap is clipped to bare chassis metal.
This paper covers the practical work of supporting, maintaining and integrating physical computer systems, the everyday responsibility a network and systems administrator carries out on the hardware every later paper in this diploma assumes is running correctly. This opening chapter names the electronic components a support technician works with directly and the tools needed to work on them safely.
Computer electronic components
A support technician thinks of a computer as four groups of electronic components, because faults, upgrades and cleaning are organised around them. Each group has its own failure modes and its own handling rules.
| Component group | Typical fault | First check |
|---|---|---|
| System unit | No power, overheating, random restarts | Power cable and switch, fans, dust |
| Secondary storage | Slow access, errors, disk not detected | Cable and connection, SMART status, backups |
| Input/output devices | Not recognised, erratic behaviour | Connector, another port, another device |
| Communication devices | No network, intermittent connection | Link light, cable, another port on the switch |
Computer maintenance tools
The right tool prevents damage as much as it enables repair. The syllabus names six, and an examiner expects each one matched to the job it is for and the harm it avoids.
Testing a suspected power supply with a multimeter
A desktop restarts at random under load. Diagnostics software shows no disk or memory errors, so the technician suspects the power supply unit.
With the machine running, the multimeter is set to DC volts, the black probe on a ground (black) pin of a spare drive power connector, and the red probe on each supply line in turn.
ATX supplies are specified to hold each rail within 5% of nominal: the +12 V line must read between 11.40 V and 12.60 V, the +5 V line between 4.75 V and 5.25 V, and the +3.3 V line between 3.135 V and 3.465 V.
The +12 V line reads 11.1 V at idle and drops to 10.6 V when the machine is loaded, well outside tolerance, while the +5 V line holds at 5.02 V. The supply is failing under load, which matches the symptom, and it is replaced.
Had every rail stayed in range, replacing the supply would have wasted money and left the fault in place; the measurement is what justifies the part.
- Disconnect mains power and press the power button to discharge the supply before opening a case
- Wear the anti-static strap clipped to bare chassis metal, and keep boards in anti-static bags until fitted
- Photograph cable positions before disconnecting them and keep screws grouped by where they came from
- Never spray chemicals into a powered device, and let contact cleaner evaporate fully before reassembly
- Record every intervention in the asset's service history so the next technician knows what has been done
Self-check
(a) Name the four groups of computer electronic components and give two examples of each. (4 marks)
(b) For each group, state one typical fault and the first check a technician should make. (4 marks)
(c) List the six maintenance tools named in the syllabus and state the job each is for. (6 marks)
(d) A desktop shuts down whenever it has been running for about twenty minutes. State which two tools would help isolate the cause and how. (4 marks)
(e) State four safety precautions when using maintenance tools inside a system unit. (4 marks)
Show worked answer
(a) The system unit: motherboard, processor (also memory, power supply). Secondary storage: hard disk, solid-state drive (also flash drives, optical discs). Input/output devices: keyboard, monitor (also mouse, printer, scanner). Communication devices: network interface card, modem (also Wi-Fi adapter, router).
(b) System unit: no power or random restarts, check the power cable, switch and fans. Secondary storage: disk not detected or errors, check the cable and SMART status. Input/output: device not recognised, try another port or another device. Communication: no network, check the link light and cable.
(c) Hand tools: disassembly and reassembly. Diagnostics software: testing components without opening the case. Multimeter: measuring voltage, continuity and resistance. Chemicals, freeze spray and compressed air: cleaning contacts, isolating thermal faults and clearing dust. Foam or lint-free swabs: cleaning sensitive surfaces without residue. Memory module tester: confirming whether RAM is faulty.
(d) Diagnostics software (the hardware monitor and event log) to read temperatures and see whether the shutdown coincides with overheating, and compressed air to clear dust if it does; or freeze spray applied to a suspected component to see whether cooling it prevents the shutdown, isolating a thermal fault. A multimeter to check the supply under load is also acceptable.
(e) Disconnect mains power and discharge the supply first; wear an anti-static strap clipped to the chassis; handle boards by the edges and keep them in anti-static bags; never spray chemicals into a powered device; photograph cabling before disconnecting. Any four.
Exam tip
Anti-static precautions and correct tool choice are favourite specific details in this chapter: static discharge from an ungrounded technician is one of the most common causes of silently damaged components during a routine repair, and an answer that names the tool without saying what harm it avoids earns only half the marks.