Why does my computer keep turning itself off for no reason? It’s not shutting down. It just turns off completely. — Sam, Apex, NC
Marshall Brain Answered:
That has got to be frustrating.
Usually if it is an operating system or driver problem, you will get a blue screen or the computer will reset and reboot. But when it just turns off for no reason… let me give you two suggestions to try.
The first thing I would do is check the CPU for overheating. If the fans inside the case stop working or the heat sink on the CPU fills with dust, the CPU will overheat and this might cause the system to shut off.
Check all the fans in your case, including the fan on the CPU, and make sure they are all spinning when the machine is on. Vacuum all the dust out of the case and from around the CPU heat sink. If it is a desktop machine this is fairly easy. With a laptop it is harder, but this video shows you exactly what can happen and how much dust can build up:
If you go to Download.com, you can find free programs that will display your CPU’s temperature. Download one of these and see what the temperature is. If it is above 50 degrees C, chances are that you have a fan problem or a dust problem and it should be relatively easy and inexpensive to fix.
[Side note - if it is a laptop and you are using it on your lap or bed, you might also check to see if your clothing or blankets are blocking an important air vent on the bottom of the machine. I once had a laptop that would spontaneously shut down if I put it on the bed for more than 3 minutes.]
The other thing to consider is the power supply. It could be failing intermittently. This can be more difficult to debug. You could buy a new power supply for $30 and swap it in, or if you have a spare case with a power supply, transfer everything to the spare case and see if the problem persists.