Computer turns off without warning
Tip: This document is for computers turn and remain off after an extended period of use. Not computer's that turn back on (restart) or computer's that shuts off immediately upon powering up.
Caution: Some of the steps below require you to work inside your computer. Before opening your case, be aware of the dangers of ESD.
Heat related issue
Most computers today are designed to turn off automatically if any of it's inner components overheat. Often, heat related issues occur when the computer is working hard, e.g. playing a graphically intense computer game.
Start by verifying the fan on the power supply is working by examining the back of the computer. The fan should be moving quickly and smoothly. All other fans in the computer require you to open your case to inspect them. Once you have access to the inside of your machine, examine the processor (heat sink), video card, and case fans. If you have heard any abnormal noises coming from your computer, such as a high squealing sound, it could be an indication of a fan malfunction.
Note: If your issues are on a laptop, we do not suggest opening the computer. Instead, verify the fan on the side of the computer is working and blowing out hot air. Also, with a laptop you may want to invest in a cooler pad to help lower its running temperature.
Tip: Working on the interior of your machine provides an opportune time to clean the inside. Dust, dirt, hair, and other trapped debris can prevent proper air flow; which may lead to overheating.
Tip: If your BIOS monitors the RPM of the fans, enter BIOS and make sure the BIOS does not report any errors. Software utilities such as SpeedFan can also be used to help monitor fans in your computer.
Tip: Check the processor heat sink to make sure that it is properly seated and has the correct amount of thermal compound.
Caution: If you do remove the processor heat sink, thermal compound should be cleaned off and new thermal compound should be applied.
Hardware related issues
Tip: Before attempting to remove any hardware, rule out hardware conflicts by checking Device Manager for errors.
Any failing hardware component in your computer could cause your computer to unexpectedly turn off without warning. If you have recently added any new hardware remove it from the computer to make sure it is not the cause of the problem.
If you have not recently installed any new hardware into the computer, the next best solution to systematically remove non-essential hardware. For example, remove your modem, network card, sound card, and any other expansion cards that are not needed for your computer to operate. Running the computer without these cards may help diagnose your issue.
Problem with UPS or surge protector
Make sure any surge protector or Uninterruptible Power Supply (UPS) is not the cause of your problem by connecting the computer directly to the power plug outlet on your wall. Also, if you have a UPS that connects a USB cable to the computer to manage power saving features, make sure it is also disconnected.
If this resolves your problem, you may have a defective surge protector or UPS. In the case of the UPS, there may be other issues such as a UPS overload or UPS drivers reporting bad power situations that cause your computer to shutdown. Make sure there are not too many devices connected to your UPS and that it has the latest software updates.
Your computer may be infected with a virus or other malware that is designed to shut down your computer upon certain conditions. If your computer seems to be turning off when executing a certain program at specific times in the day, it could be infected.
If after following each of the previous recommendations your computer still continues to reboot, it is likely that you are experiencing a Microsoft Windows operating system related issue that cannot be explained. To help make sure this is the case, try the steps below.
- Reboot the computer and enter CMOS setup as the computer is booting.
- After you have loaded the computer in CMOS setup, let the computer sit.
If the computer does not turn off while letting the computer sit in CMOS, you are likely experiencing an issue with Microsoft Windows or your operating system and it is recommend you erase everything and reinstall Microsoft Windows.
If after reinstalling your operating system, or during the installation of your operating system, your computer turns off abnormally, it is very likely that other hardware is failing in the computer. Often this is RAM, CPU, Motherboard, Power Supply, or Video card (in that order).
If you have extra parts or have a friend or co-worker with a similar configuration that is willing to allow you to test their hardware in your computer, try swapping these parts to determine if they are at fault. Otherwise, you need to have the computer serviced.