My PC Shuts Down Alone: Causes and How to Fix It

When it shuts off: the key clue

Timing tells almost everything: shuts off gaming or under load means heat or tight PSU. Shuts off idle or always after the same minutes means failing PSU or scheduled shutdown. Fully random means RAM or board. Note the pattern before touching anything: it solves half the diagnosis.

Overheating (cause #1)

PCs shut down to avoid frying (thermal protection around 100 ºC on CPU). Download HWiNFO or Core Temp (free) and watch temps under load: sustained readings above 90 ºC mean trouble. Fixes in order: clean dust from fans and grilles with compressed air, check all fans spin, and if it's years old, replace thermal paste (cheap, but get help if you've never done it).

Borderline power supply

If you upgraded GPU or disks and the PSU stayed, the PC dies on power spikes. Estimate your real draw (there are online PSU calculators) and compare with your PSU label: if it's tight or the unit is 6+ years old, it's the prime suspect. A decent 550-650W Bronze PSU costs $50-70.

Software causes

Before buying anything, rule out: Windows Event Viewer (look for critical Kernel-Power 41 right at shutdown time), a full antivirus scan (guide here) and updated GPU drivers. Also check for scheduled shutdowns (scheduled tasks or vendor software with aggressive "eco mode").

When to call a technician

If temps are fine and it keeps shutting off, or Event Viewer shows Kernel-Power with no clear pattern, you need a spare PSU to test plus RAM/board testing: that's bench work. We do it with you in the free diagnosis.

FAQ

Why does it shut off only when gaming?

Almost always heat or a tight PSU: games max out CPU/GPU and trip both protections.

Can it be a virus?

Rare but possible (miners). A full scan rules it out in 30 minutes.

What temperature is dangerous?

Sustained CPU above 90-95 ºC or GPU above 85-90 ºC: the PC will shut down to protect itself.

Is replacing the PSU worth it?

If it's the cause, yes: $50-70 and the PC revives. If not, money wasted: diagnose first.

Related guides

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