Computer shuts down or restarts by itself: how to find the cause
You are working or gaming and the computer suddenly goes dark or restarts. It is not a “glitch”: there is always a reason, and it is usually one of four. Here is how to tell them apart.
Four main causes
- Overheating. The processor or graphics card hits its limit and the computer switches off to protect itself. Sign: it goes off under load — in a game, a video, while archiving — and starts again after a pause.
- Power supply. A weak or old unit cannot handle the load. Sign: it switches off instantly, as if unplugged, especially in games.
- Drivers and Windows. A driver error gives a blue screen and a restart. Sign: it restarts on the same action every time.
- Memory or drive. Memory errors and a dying drive cause random restarts and freezes.
What to check yourself
- Feel the bottom of the laptop and listen to the fan: if it roars and the bottom is hot, that is overheating.
- Look for dust on the vents of the PC or laptop.
- Remember what changed: a new graphics card, a Windows update, a new program.
- Plug the computer straight into the wall, without an extension lead.
How I find the cause
I check the Windows event log and error codes, temperatures under load, and the health of the drive and memory. That way the cause is found precisely, not by “let’s try replacing this”. Overheating from dust is solved by cleaning the cooling system; I replace thermal paste only if I see during cleaning that it has dried out.
If the PC power supply is to blame, I tell you which one to buy and fit it. If a laptop fan or the board is faulty, that is a job for a service centre with equipment — I will point you there.
A case from practice
A gaming PC kept stuttering and crashing with a blue screen — Windows had been reinstalled, it did not help. The culprit was the M.2 drive: the full story. That is why I always check the hardware before reinstalling the system.