The ₹85,000 Lab Upgrade: SSD, RAM or New Desktops?
Sunrise Junior College runs a computer lab with 12 desktop PCs bought in 2019. Each has one 4 GB DDR4 stick, a 500 GB hard disk, integrated graphics and 64-bit Windows 10. Machines take more than three minutes to reach the desktop, and opening a browser with five tabs freezes one for about a minute. Two PCs no longer reach the BIOS at all, and one gives off a burning smell near the power supply. The lab has ₹85,000 to spend. A vendor quotes ₹2,000 per 4 GB DDR4 stick, ₹2,600 per 240 GB SATA SSD, and ₹32,000 for a new entry-level desktop. Every cabinet has two RAM slots and one slot is already occupied. The principal's instruction is: 'Buy the two new computers first, then spend whatever is left on upgrading the old ones.' The lab supervisor has asked you to sanity-check that plan before the purchase order is signed.
1. Evaluate the principal's instruction and recommend how the ₹85,000 should actually be allocated. Justify the order of upgrades using the symptoms described.
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Separate the three different faults first.
- Two PCs that never reach BIOS - a POST failure (power supply, loose RAM, motherboard). No software or disk upgrade revives these; they are replace-or-diagnose cases.
- One burning smell near the PSU - a failing power supply. Stop using it immediately; do not open or 'test' it.
- Nine slow PCs - a 3-minute boot and one-minute freezes with five browser tabs is the classic signature of a 500 GB mechanical disk serving as the page file, made worse by only 4 GB of RAM.
Check the arithmetic of the proposed plan. 2 × ₹32,000 = ₹64,000, leaving ₹21,000. That buys 8 SSDs (8 × ₹2,600 = ₹20,800) and nothing else - not 12, and no RAM. So the principal's order leaves 4 of the slow machines untouched and gives the lab the smallest benefit per rupee on the machines that still work.
Judgement. The bottleneck on the working PCs is the disk, not the CPU: a 240 GB SSD fixes boot time and application loading on 8 of the 9 slow machines for ₹20,800. Adding 4 GB RAM to all nine would cost ₹18,000 but leaves the disk bottleneck intact, so boot stays slow even if tab-switching improves.
Recommendation: buy the two replacement desktops (₹64,000) plus eight SSDs (₹20,800), which fits ₹85,000 with ₹200 to spare; schedule RAM for the next budget cycle. Before any RAM order, confirm DDR generation and per-slot maximum from the board manual, not from a vendor quotation that only says '4 GB stick'.
2. The vendor is also pushing 12 extra 4 GB RAM sticks. What must be verified before that order is placed, and what is the consequence of each mismatch?
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A RAM order that only says '4 GB' is not a specification. Check, in this order:
- DDR generation (DDR3 vs DDR4 vs DDR5). The notch position differs, so the wrong generation physically will not seat - and forcing it damages the slot. The 2019 purchase date suggests DDR4, but verify per machine with the board model or CPU-Z, because a mixed lab is common.
- Form factor. Desktop DIMM vs laptop SO-DIMM. They are different lengths and are not interchangeable.
- Free slots and channel layout. Each cabinet has one of two slots occupied. A single extra stick gives 8 GB in single-channel mode; two matched sticks give 8 GB dual-channel with better integrated-graphics performance. The quote for '12 sticks' implies one per machine, which is a single-channel outcome.
- Per-slot and total maximum supported by the board and chipset. Some older boards cap at 8 GB total; a 4 GB stick then buys nothing.
- Speed and timings. Mixing a 2400 MHz stick with a 2666 MHz stick makes the pair run at the slower speed. Mixing brands usually works but is not guaranteed.
- Operating system bitness. 32-bit Windows sees roughly 3.2 GB of any RAM installed, so buying beyond 4 GB would be wasted on such machines.
- Buffered/ECC vs unbuffered non-ECC. Server ECC modules will not work in consumer desktops.
Consequence framing: items 1, 2 and 7 stop the machine from booting at all; items 3, 4 and 5 silently deliver less than the money spent; item 6 silently wastes the purchase. Ask for the exact part number and warranty in writing before approving.
3. Describe what should be done with the machine that smells of burning and the two that do not POST, and explain why a Windows reinstall is not the answer.
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Triage by symptom type. No POST and a burning smell are power-and-hardware faults; reinstalling the operating system requires the machine to boot from external media, which these three cannot do. A reinstall would also destroy the data on a machine that may only need a reseated module.
The burning smell machine - safety first.
- Switch it off at the wall, unplug it, and do not power it on again. A failing PSU can fail short and take the motherboard and drive with it.
- Do not open the PSU casing: charged capacitors hold voltage after unplugging.
- Label it 'do not use', move it away from other equipment, and replace the PSU or scrap the unit.
The two non-POST machines - cheap checks before condemning them.
- Listen for the POST beep pattern and note it; a repeated beep usually points to RAM.
- Reseat and swap RAM sticks, and try one stick at a time in slot 1.
- Check the 24-pin and 4/8-pin CPU power connectors are fully seated, and test with a known-good PSU.
- Clear CMOS, then check whether the fans spin and whether the monitor cable and input source are correct (a dead display is easily mistaken for a dead PC).
Judgement: if a known-good PSU and single stick produce no POST beep and no display, the board or CPU has failed - replacing it is not economic at ₹32,000 for a whole new unit. Record the diagnosis, harvest the working RAM and disks as spares, and send the dead units to a registered e-waste channel rather than the general bin.