Six Weeks to Exam: Upgrading an Aging School Computer Lab
St. Xavier's Higher Secondary School has a computer lab with 24 desktop PCs purchased in 2016: Intel Core i3-6100, 4 GB DDR4 RAM, 500 GB 7200 rpm HDD, 450 W unbranded PSU, and Windows 10 Home 64-bit. The IT elective class of 40 students now uses Python 3, LibreOffice, and browser-based practice tests. Teachers report that machines take 4–6 minutes to boot, freeze when Chrome has more than six tabs open, and sometimes restart during practical work. The principal has ₹60,000 and wants 'the maximum number of machines fixed'. A vendor quotes ₹3,200 per 4 GB RAM stick, ₹2,800 per 240 GB SATA SSD, ₹4,500 per branded 450 W PSU, and ₹1,200 per UPS battery replacement. The lab has 24 working UPS units but 9 batteries are more than four years old. The school also has 5 unused 2 GB DDR4 sticks and one spare 1 TB HDD. The exam is in six weeks. Propose a plan that improves exam reliability without pretending all 24 machines can be fully refreshed.
1. Classify each reported symptom - slow boot, freezing with many Chrome tabs, and random restart during practical work - as most likely caused by storage, RAM, power delivery, or software. State which single upgrade you would apply lab-wide first and justify it with the evidence.
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Slow boot (4–6 minutes): storage is the strongest suspect. A 7200 rpm HDD from 2016 plus Windows startup services explains long boot and slow application launch far better than an i3-6100, which is still adequate for Python and LibreOffice.
Freezing with six Chrome tabs: RAM pressure is the primary cause, made worse by the page file sitting on that same HDD. 4 GB is below comfortable for Windows 10, Chrome, Python, and LibreOffice at once.
Random restart: this is not a normal low-RAM symptom. It points to power delivery - an unbranded 450 W PSU, a failing UPS battery, or both - or to overheating. Software crashes usually close an application, not restart the whole PC.
First lab-wide upgrade: SATA SSDs. Every one of the 24 machines must boot and load software from disk, so the SSD improves the symptom that affects every practical session and is measurable within a day. RAM is second because it fixes the multi-tab freeze. PSU or UPS work should be targeted only at machines that actually restart, after swapping the PC onto a known-good UPS to identify the culprit. Software cleanup (startup apps, malware scan, updates) should precede any purchase because it is free.
2. Allocate the ₹60,000 across the 24 PCs. Show the arithmetic, state how many machines receive each upgrade, and explain what you deliberately leave unfixed.
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One workable allocation:
- 12 × 240 GB SSD at ₹2,800 = ₹33,600
- 6 × 4 GB RAM at ₹3,200 = ₹19,200 (upgrades those six from 4 GB to 8 GB)
- 2 × UPS battery at ₹1,200 = ₹2,400
- 1 × branded 450 W PSU at ₹4,500 = ₹4,500
- Total = ₹59,700, leaving ₹300.
The logic is to create 12 'exam-ready' machines with fast storage, give 8 GB RAM to the six most heavily used machines, replace the two most dangerous UPS batteries, and hold one PSU for the PC that restarts most often. The remaining 12 PCs are not fully refreshed. They can serve as fallback units or run lighter tasks such as attendance entry. I deliberately do not buy 24 SSDs, because 24 × ₹2,800 = ₹67,200 exceeds the budget before any RAM or power work. I also do not spend ₹4,500 on a PSU for every machine: random restarts must first be diagnosed as PSU versus UPS, otherwise the school replaces working parts. If the restarts stop after a UPS battery swap, the PSU money can be redirected to one more SSD.
3. A teacher suggests using the five spare 2 GB DDR4 sticks to give five PCs 'free extra RAM'. Give two technical reasons this is a poor decision in the six weeks before the exam.
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First, adding a 2 GB stick to an existing 4 GB stick produces 6 GB in an asymmetric configuration. The memory controller may run all modules at the slower speed and with less favourable timings, and some motherboards become unstable with mixed ranks, brands, or speeds. A lab PC that passes a five-minute test can still fail under a two-hour practical load.
Second, 6 GB is still below the comfortable level for Windows 10, Chrome, Python, and LibreOffice, so it does not remove the freezing symptom. It also consumes a DIMM slot that could later take a matched 4 GB stick for 8 GB. The 'free' sticks are untested, may be out of warranty, and cost technician time to install and test on five machines. In exam week, an unstable 6 GB machine is worse than a stable 4 GB machine, because a crash can corrupt a student's saved practical file. The spare 1 TB HDD is similarly not a free speed upgrade; it may add storage but not reduce boot time.