The Overloaded School Computer Lab
A secondary school in Malta has 24 desktop computers in its computing lab. Each machine has a dual-core CPU, 4 GB of RAM, a 500 GB mechanical hard disk and a 32-bit version of Windows 10. Teachers report that booting takes over three minutes, and that switching between a web browser with ten tabs and a block-based programming environment causes the screen to freeze for several seconds. The school has €2,000 for upgrades and cannot replace the machines this year. The IT coordinator proposes spending the whole budget on new 1 TB solid-state drives, arguing that storage is the main problem. The head of school wants evidence before approving the purchase, and asks whether the existing 4 GB of RAM is adequate. One teacher suggests installing a 64-bit operating system, but is unsure whether the CPUs support it.
1. Identify the most likely performance bottleneck or bottlenecks and evaluate the IT coordinator's proposal to spend the entire €2,000 on 1 TB SSDs. Refer explicitly to the symptoms described.
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The symptoms point to two related bottlenecks, not one.
- A boot time of over three minutes is typical of a mechanical hard disk with a fragmented or heavily used Windows installation. An SSD would reduce this dramatically because random reads are much faster.
- Freezing when ten browser tabs and a block-based IDE are open is a memory-pressure symptom. With 4 GB of RAM, Windows begins paging to disk, and the machine appears to freeze while pages are swapped. An SSD makes paging faster, but it does not remove the cause: there is still too little RAM for the working set.
The proposal therefore treats only part of the problem. It is also poor value: 1 TB per lab machine is far more capacity than needed for an operating system and a few applications, and 24 such drives would consume the whole budget while leaving the RAM bottleneck. A smaller SSD plus a RAM upgrade would address both symptoms for less money. The 32-bit operating system is a further constraint, because it cannot make effective use of more than about 3.2–3.5 GB of RAM. Spending on RAM before checking and changing the operating system would waste money. The correct judgement is that SSDs are useful but the proposal is incomplete and not cost-effective.
2. Recommend an upgrade plan within €2,000 for all 24 machines, in priority order. Justify each choice with reference to the symptoms and constraints, and state any assumptions about prices.
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A defensible plan needs an audit first, because the 32-bit limit changes the order of work.
- Check whether each CPU supports 64-bit operation, using the manufacturer's specification or a tool such as CPU-Z. Most dual-core CPUs of the last fifteen years do, but the school should not assume it. Also check the number of free RAM slots and the maximum RAM supported by the motherboard.
- If 64-bit is supported, install 64-bit Windows 10 and then add RAM to reach 8 GB per machine. This directly addresses the freezing. If 64-bit is not supported, a RAM upgrade beyond about 3.5 GB is wasted, so the school must either accept the limit or replace those machines.
- Fit a 240–256 GB SSD in each machine. This addresses the three-minute boot and also softens any remaining paging.
A realistic budget is about €20–€30 per 4 GB DDR3 module and €25–€35 per 240 GB SSD, so 24 machines cost roughly €1,100–€1,600, leaving contingency for cables, brackets and failed parts. Labour can be done in-house. The priority is to remove the 32-bit cap before buying RAM, then fit RAM and SSDs together. Buying 1 TB drives would exceed the benefit and leave no budget for the memory problem.
3. Explain why installing a 64-bit operating system matters here, and what could go wrong if the school installs one without checking the hardware. Include the maximum RAM usable by 32-bit Windows 10 in your reasoning.
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A 32-bit version of Windows 10 has a 4 GB virtual address space, and after hardware reservations the usable physical RAM is typically about 3.2–3.5 GB. Any RAM above that is not available to applications, so upgrading a 32-bit machine to 8 GB gives little or no benefit. A 64-bit operating system can address far more memory and allows each process to use more than 2 GB, which matters for a modern browser with many tabs. That is why the 64-bit question must be settled before the RAM purchase.
The risk is that 64-bit installation requires a 64-bit-capable CPU, suitable firmware, and drivers for peripherals such as printers or graphics adapters. If the CPU is not capable, the installation will fail. If drivers are unavailable, devices may stop working. The school should also check the motherboard's maximum RAM and free slots, and back up pupil data before reinstalling. Installing 64-bit Windows is not itself a performance upgrade; it is an enabling change that makes a RAM upgrade meaningful. Without it, the €2,000 plan would be built on a false assumption.