The Overheated School Computer Laboratory
Northgate Junior Secondary has 28 donated desktop computers in one laboratory. Twelve have 2 GB RAM and 160 GB hard disks; sixteen have 4 GB RAM and 500 GB hard disks. All run a 64-bit operating system and an office suite. During afternoon practicals, eight machines shut down without warning after 10 to 20 minutes, two reboot repeatedly before the login screen, and one emits a repeating beep pattern with no display. The laboratory has one shared 1.5 kVA UPS, the ambient temperature reaches 33 degrees Celsius, and dust covers the floor vents. The school can spend 9,000 currency units this term, either on repairs or on four refurbished 8 GB machines. Teachers report losing unsaved work. The timetable requires 30 learners per practical, so every working machine matters. The technician has a power-supply tester, spare RAM sticks, thermal paste, and compressed air, but no spare motherboards.
1. Recommend an ordered diagnostic and repair plan for the three symptom groups. Justify the order using likelihood, risk to data, and cost.
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Make the laboratory safe and protect data first: ask learners to save to a network folder or USB stick, then power off and unplug each faulty machine. Record the beep pattern and consult the motherboard or BIOS documentation if available; beep codes are vendor-specific, so do not assume one meaning. Next tackle the eight shutdowns as a group because they are the largest loss of seats: clean dust from vents, fans and heat sinks, confirm fans spin, test the power supply under load with the tester, and reseat RAM. Replace only power supplies that fail. Then investigate the two boot loops, trying a known-good power supply and one RAM stick at a time before repairing the operating system. Finally diagnose the no-display machine by reseating or swapping RAM, then testing the video output. Change one variable at a time and label parts. This order restores the most machines for the least money, reduces heat and power risk, and avoids unnecessary motherboard replacement.
2. The head teacher proposes spending all 9,000 currency units on four refurbished 8 GB machines. Evaluate this against repairing existing machines and recommend a mixed plan.
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Four refurbished machines would give about 21 working computers (17 reliable plus 4), still nine short of the 30 required, and they may not match the existing software image. Spending all 9,000 on them also leaves the 11 faulty units unrepaired. A better plan is to repair the cheapest high-yield faults first: cleaning and power-supply replacement for the eight shutdowns, RAM or operating-system repair for the two boot loops, and RAM testing for the beep unit. If, for example, eight can be restored for 3,000, the school has 25 working machines and 6,000 left. Buy two refurbished 8 GB units for the heaviest tasks and keep a small reserve for UPS batteries or replacement fans. The 2 GB units can run the office suite but should not be used for browser-heavy work. The mixed plan improves seats, keeps spares, and addresses the 33 degree heat that likely caused the shutdowns.