Day 3: Physical Assembly | Build a PC in 5 Days

Before You Touch Anything

Anti-static precautions: touch a metal part of the case or PSU (with it unplugged) before handling components. An ESD wrist strap is ideal. Never work on carpet. Keep components in anti-static bags until installation. Handle PCBs by the edges, not the chips. CPUs are the most static-sensitive and most expensive single component.

CPU, RAM, and Cooler

CPU install: lift the socket lever, align the notch/triangle marker, lower the CPU (don't force — it drops in by gravity on AM5, has lever mechanism on LGA1700), lock the lever. Thermal paste: pea-sized dot in center of CPU IHS, or spread thin across the surface. The cooler pressure spreads it. RAM: push straight down into A2/B2 slots until both clips click. Requires significant force — push firmly.

Motherboard, GPU, and Cables

Mount the I/O shield in the case first. Install motherboard standoffs (they raise the board off the case, preventing shorts). Screw in the motherboard. GPU: open PCIe x16 slot latch, seat the card, push down until it clicks, close the latch. Connect PCIe power cables. Power cables: 24-pin ATX power, 8-pin CPU power (top of board), SATA data and power for any 2.5"/3.5" drives. M.2 drives screw directly to the motherboard.

bash

#!/bin/bash
# Post-build verification checklist
# Run these commands after first boot to verify everything is working

echo "=== CPU Info ==="
lscpu | grep -E 'Model name|CPU\(s\)|Thread|Core|MHz|cache'

echo ""
echo "=== RAM Info ==="
dmidecode -t 17 2>/dev/null | grep -E 'Size|Speed|Type|Locator' | head -20
# or on modern systems:
cat /proc/meminfo | grep -E 'MemTotal|MemFree|MemAvailable'

echo ""
echo "=== Storage ==="
lsblk -d -o NAME,SIZE,TYPE,ROTA,TRAN
# ROTA=0 means SSD, TRAN=nvme means NVMe

echo ""
echo "=== GPU ==="
lspci | grep -i 'vga\|3d\|display'

echo ""
echo "=== Temperatures ==="
# Install: sudo apt install lm-sensors && sudo sensors-detect
sensors 2>/dev/null || echo "Install lm-sensors: sudo apt install lm-sensors"

echo ""
echo "=== Disk Write Speed (quick test) ==="
dd if=/dev/zero of=/tmp/speedtest bs=1G count=1 oflag=dsync 2>&1 | tail -1
rm /tmp/speedtest

💡

If the PC won't POST (no image, no beeps), the most common causes are: (1) RAM not fully seated — push harder, (2) CPU power cable not connected — there's both a 24-pin and an 8-pin, (3) GPU PCIe power cable missing. Check these three first, in this order.

📝 Day 3 Exercise

Document Your Build Process

Before assembly: take photos of all component packaging and note the exact part names for warranty purposes.
During CPU install: photograph the socket before and after. Verify no bent pins (Intel) or missing pins.
After assembly: before powering on, do a paper clip test on the PSU — short the green wire to any black wire in the 24-pin connector to verify PSU turns on without a motherboard.
First boot: does POST complete? Do you see the BIOS splash screen? Note any POST codes on the motherboard's LED display.
Run the verification script above (on Linux). Verify all components are detected: correct RAM amount, NVMe drive, GPU.

Day 3 Summary

Anti-static handling is non-negotiable — ESD can silently damage components without obvious failure
CPU thermal paste: pea-sized dot, let cooler spread it; too much is worse than too little
RAM requires firm downward pressure to seat — both clips must click; A2/B2 slots for dual channel
No POST? Check RAM seating, CPU power cable, and GPU power in that order — these cause 90% of first-boot failures

Challenge

Build a PC on pcpartpicker.com using only used/refurbished parts from eBay with a $400 budget. What's the best gaming build you can configure? What compromises did you make? What are the risks of buying used PC components, and how would you test them before committing?

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Day 2: Compatibility Deep Dive

Day 4: BIOS Setup and OS Install

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