What is a BSOD? (Blue Screen of Death)
A BSOD is the error screen Windows shows when it hits a fault so serious that it has to stop to protect your data and hardware. The PC restarts afterwards, and the screen includes a stop code that points to the cause.
What the stop code tells you
Every blue screen shows a short code such as MEMORY_MANAGEMENT, CRITICAL_PROCESS_DIED or WHEA_UNCORRECTABLE_ERROR. Take a photo of it before the PC restarts, because it narrows the fault down faster than anything else. On newer versions of Windows 11 the screen is black rather than blue, but it means the same thing.
Common causes
Faulty or badly seated RAM, a failing SSD or hard drive, a bad driver after an update, overheating, or an unstable PSU. A single blue screen after an update is usually harmless. Blue screens that keep coming back, or that appear only in games, almost always trace to hardware.
When it needs a repair
If the PC blue-screens more than once a week, will not finish starting Windows, or shows a different stop code each time, stop using it for important work and have it tested. Repeated crashes can corrupt files. We test the memory, storage, temperatures and power supply to find which part is at fault before anything is replaced.