If your computer keeps shutting down and restarting, the problem can be more that just loose connections or a computer virus. This article includes some common steps that are to be considered, if your computer keeps shutting off on its own. You are working on a very important assignment and suddenly, you desktop computer shuts down. You can imagine how irritating can it be. What would you do if your computer keeps shutting down randomly? There are many types of computer problems, and the system shutting down and restarting automatically is one which is certainly annoying. There can be many reasons why your computer keeps shutting down automatically and reboots again. If you are asking yourself 'why my computer keeps shutting down by itself', you first need to diagnose the exact cause of the problem and then carry out the computer repair accordingly. Let us understand the steps you need to take if your computer keeps shutting down and restarts automatically. Why Does the Computer Keeps Shutting Down and Reboots? Computer Virus There are higher chances of a computer shutting down due to the interference of a computer virus. The virus gets into the computer and fiddles with crucial sections of the operating system, which may cause the system to shut down automatically. You need to install a good antivirus software and get the computer scanned thoroughly for any malware and viruses. Also see to it that the operating system and all hardware drivers are updated. Power Supply The computer power supply unit is an equipment that is installed in the cabinet to provide power to the system for operation. Your computer can shut down, if there is not enough power supplied to it for handling the programs running. If you are using the computer for running intensive software such as PC games, the system would require more power than what is actually available. Another reason can be overheating of the power supply. After the power supply is used for a substantial period of time, there is a possibility of dust getting collected inside it. And this may cause it to overheat, resulting in the shutdown of the desktop computer. If the power supply is at fault, you may need to get a new one installed. Overheating of the Motherboard and the Processor As with the case of dust getting collected in the power supply, the computer motherboard and the processor can also collect dust, which may be the reason for their overheating. This may also be one of the reasons why your computer keeps shutting down and restarting. You need to open the computer cabinet and clean the dust off the computer parts. The CPU board and the processor can also overheat because of many applications running. If this is the case, then it is suggested to keep the running of applications as less as possible or increase the size of Random Access Memory (RAM). Bad capacitors on the motherboard is also one of the reasons, why your computer keeps shutting down very often. The 'Automatically Restart' Setting If you are using Windows XP operating system, there is a setting that indicates the computer to reboot if it detects an error in the system's operation. In order to check if this is the problem, click on 'Start' and 'Control Panel', then select 'Performance and Maintenance'. Click on 'System', then the 'Advanced' option, and select 'Settings' from the 'Startup and Recovery' section. You will find an 'Automatically restart' option, which you need to uncheck for preventing the system from rebooting. Read more on computer keeps restarting on its own. These were the possible reasons, why your computer keeps shutting down and rebooting. You also need to check if the power cables are properly connected to the cabinet and to the UPS, as loose connections can also be a reason for system shutdown. The most common cause of the computer getting shut down or restarted is due to overheating of the power supply and other internal computer parts.