My six-year-old PC randomly powers off after running for roughly 15 minutes, although sometimes it happens sooner. I already replaced the power supply, but the problem continued. The GPU seems to be working normally while the system is running, so I'm wondering whether the issue could be overheating, the CPU cooler, motherboard, RAM, or something else. I've also left the computer unplugged for about 20 minutes, but that didn't change anything. What should I test before replacing more parts?
4 Answers
Run a hardware monitor such as HWiNFO immediately after booting and watch the CPU temperature, motherboard temperatures, fan speeds, and voltages. You can also check Reliability Monitor or Event Viewer for hardware errors and unexpected shutdowns. If the computer turns off before the monitoring tools load, that points more strongly toward a hardware or thermal problem.
Make sure this is actually a shutdown rather than the computer waking or restarting unexpectedly because of a USB device or power-management setting. However, since it consistently runs for only a short time, overheating or a failing component is more likely than a sleep-mode issue.
Disconnect all unnecessary USB devices and test the PC with only the keyboard, mouse, and monitor connected. A short circuit, faulty peripheral, bad RAM, motherboard failure, or unstable power circuitry could all cause sudden shutdowns. If possible, testing with known-good RAM or another compatible motherboard would help narrow it down.
Check the CPU temperature first. A clogged heatsink, failed CPU fan, loose cooler, or dried-out thermal paste can make the system shut down for protection once it gets too hot. Clean out the dust and confirm that all fans are spinning. If the temperatures are normal, reseat the RAM and test one stick at a time, reset the BIOS to its default settings, and inspect the motherboard for visible damage.
I’ll try monitoring the temperatures and checking the reliability history before replacing anything else.