- Check the power supply also called as SMPS (Switch Mode Power Supply) at the back side of the cabinet where you connect the power chord from main power board. If the power supply is overheated or the fan of the power supply is not rotating, then you have to replace the power supply.
- Check the heat sink fan placed on the processor. The fan should be rotating constantly when you switch on the computer. If not, check the heat sink fan power connection on the motherboard. Remove the fan power connection and plug it back. If still nothing happens, replace the heat sink fan. Remember to apply heat sink paste also called as heat sink compound solution between the heat sink fan and the processor in-case if you replace the fan.
- Clear all the dust occupied inside the computer. Turn off the computer and open the CPU cabinet and blow off the dust present in the cabinet and make sure that all the connections are intact before switching on the computer.
- Remove the RAM and clean it with soft cloth. Plug it back to the original position in the motherboard
- Check for any virus or spyware present in the computer by scanning with antivirus and antispyware. You can download free Avira Antivir Personal antivirus and Arovax Antispyware programs.
- There are chances of computer turning off automatically if some of your operating system files are corrupt. If so repair the operating system files using your operating system CD/DVD.