Laptop turns on and off randomly, when your laptop develops this type of fault, it is usually a tiring and very frustrating experience especially if the occurrence is frequent and within short intervals, it disrupts your work and generally makes life very uncomfortable for you, when using the laptop.

There are quite a number of faults that can cause a laptop to randomly shut down or turn off, it could be an overheating processor, faulty memory module or a failed motherboard. Pin pointing the exact cause of the problem will require proper and careful troubleshooting until we arrive at the cause of fault. Let’s now take a closer look at some of these faults and at the same time also try and provide solution to the problem.

Possible Faults

1.Overheating processor due to the build up of dust internally, leading to the clogging of the fan.
2.Faulty memory module
3.Virus attack on the system
4.A failed motherboard

Solutions

1.To handle the overheating problem, the first step is to look for a good brush and clean the processor, the fan, heat sink and possibly the entire motherboard. The cleaning will remove dust particles that have been gathered by the laptop over a long period of time.

2.The accumulation of this dust particles leads to clogging of the fan, which in turn causes overheating of the processor ultimately leading to the laptop shutting down randomly whenever it gets excessively hot. A simple routine cleaning like the one mentioned above will solve the problem, also it doesn’t stop there it is advisable for you to repeat the procedure periodically to keep the laptop clean and functioning well.

3.This problem could be related to the memory failure. It’s possible one of the memory modules failed and because of that the laptop turns on and off randomly. In this case you can try reseating memory modules to make sure they are making good contact with the slot. You can try removing memory modules one by one and test the laptop with only one memory module installed. You can try replacing memory modules with new modules.

4.Ensure that the antivirus software on your laptop is up to date, run it to remove any virus that might infected the laptop. This is essential because the presence of virus can terribly slow down and eventually cause the laptop to shut down randomly.

5.If non of these steps is able to rectify the problem, then you have a motherboard failure.

Source: http://learnlaptoprepair..com/2013/07/how-to-repair-laptop-that-turns-off-or_13.html