Blue Screen (BSOD) Troubleshooting

Problem

A Windows machine crashes to a blue screen with a stop code, either occasionally or repeatedly.

Symptoms

• Sudden crash with a stop code (e.g. IRQL_NOT_LESS_OR_EQUAL)
• Automatic restart after the crash
• Recurring crashes under specific conditions (e.g. waking from sleep)

Possible Causes

• Faulty or outdated driver, especially graphics or storage
• Failing RAM
• Overheating
• Corrupted system files
• Incompatible recently installed hardware or software

Diagnostic Steps

1. Note the exact stop code shown on the blue screen
2. Check Event Viewer > Windows Logs > System for the matching crash event
3. Check what was installed or changed recently (driver, Windows update, new hardware)
4. Run Windows Memory Diagnostic if RAM is suspected

Commands & Tools

Step-by-Step Solution

1. Update or roll back the specific driver named in the crash dump
2. Run sfc /scannow followed by DISM to repair system files
3. Test RAM with Windows Memory Diagnostic; reseat or replace faulty modules
4. Check thermals if crashes happen under load — clean vents, reapply thermal paste if needed
5. As a last resort, do a clean OS reinstall after backing up data

Verification

The machine runs under normal and heavy load (e.g. an hour of typical use) without crashing again.

Common Mistakes

• Reinstalling Windows before checking the actual stop code and driver history
• Ignoring a recently installed driver as the likely cause
• Not checking temperatures on a machine crashing specifically under load

Escalation Criteria

Prevention

Keep drivers current through official vendor channels, avoid unverified driver download sites, and monitor system temperatures on aging hardware.

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