Computer Auto re-start without warning

Hardware issue or error

Caution:Some of the steps below require you open your computer. While in the computer, be cautious of ESD.

Any failing hardware component in your computer could cause your computer to unexpectedly create  an error or restart  without warning. If you have recently add a new hardware device, remove that device to make sure it is not causing your issues.

Make sure you are not unconstrained any hardware conflicts by viewing Device Manager for errors.

New drivers can also cause this issue, if you have recently performed any hardware driver updates you may want to try an earlier version of the drivers.

Heat Retaliated Issue
 

Many computer today are designed to turn off or automatically reboot if the computer, processor, or other device in your computer gets to hot. If you have heard any abnormal noises coming from your computer recently such as a high squealing this could indicate a fan may be failing in your computer.

First, verify the fan on the power supply is working by examining the back of the computer and seeing if the fan is moving and moving smoothly. For all other fans in the computer you need to either open the computer and verify all fans are working, e.g. processor fan and case fan.

Tip: If your BIOS monitors the RPM of the fans enter CMOS Setup and verify it does not report any errors.

Note: If this is a laptop computer, there is still a fan located on one of the sides of the laptop that can be checked. Make sure this fan is blowing or that you can feel hot air coming from the laptop. You may also consider getting a cooler pad if you find your laptop is getting hot often.

Computer virus

Computer Virus

Computer Virus

Computer viruses such as the blaster virus are written to reboot your computer without warning. Usually these viruses make the computer reboot every 5, 10, 15 or 30 minutes after the computer has booted.

If you believe your computer may be infected with a virus or are uncertain if your computer is infected with a virus make sure your virus scanner definitions are up to date.