When a computer freezes and reboots, it is difficult to discern what the problem is without some process of elimination. There could be various reasons for the computer rebooting itself - software and hardware.
Your first thought should be did you install any new hardware/software in your computer before this behaviour started? If the answer is yes, remove the newly installed device and see if your computer stops acting up. If you haven’t installed any new hardware/software then, you should look into your drivers and operating system updates. Keeping your system up-to-date with its drivers and service packs is essential to a properly working computer.
Hardware problems are more probable when computer reboots randomly with no pattern in relation to the problem or problems combination, you are running at the time. A noisy power supply, loose screw under the motherboard, bad CPU fan, and memory, expansion boards, socketed chips, and cables that are not fully seated are among the common causes. The motherboard could be cracked-these are usually hard to find.
Overheated CPU is a frequent problem cause. Be sure all air vent pathways are clear for at least several inches outside the machine. Check inside of your fan and case, and especially around the CPU heat sink for dust or pet hair. Replace CPU fan and/or add a Case fan. Clean is important. Try checking the system health in the BIOS for the processor or system temperature. You’d like it to be less than 50d Celsius, anything over 75d is running dangerous.
You can also use for the advance troubleshooting a free hardware monitoring utility SpeedFan, that will help you to read the temperatures of your motherboard and your hard disk, read voltages and fan speeds and check the status of your hard disk using S.M.A.R.T. or SCSI attributes.
Also a bad memory chip can do this. Remove one at a time or replace the current module and run the computer. Free utility from Microsoft might help you on this stage of the memory investigation. The Windows Memory Diagnostic tests the Random Access Memory (RAM) on your computer for errors. The diagnostic includes a comprehensive set of memory tests. If you are experiencing problems while running Windows, you can use the diagnostic to determine whether the problems are caused by failing hardware, such as RAM or the memory system of your motherboard.
Power problems such as a very brief loss of power can cause the computer restarting as well. We recommend always plugging your computer into a UPS (Uninterruptible Power Supply). It is clear that the same bad outcome can be caused by intermittently failing power supply.
Disabling automatic restarting option
When a Stop error occurs, by default XP is set to restart. This makes it hard to troubleshoot the error. To change this behavior, perform the following operation:
* Right click on My Computer and select properties.
* Click Advanced tab.
* Click Settings under Startup and Recovery.
* Under System Failure uncheck Automatically Restart.
* Click OK.
This will not solve your problem, but will instead give you a BSOD (Blue Screen of Death). At which point Windows will give you a vague error, at which point we can trace your problem. You can note the error ID and try to troubleshoot the problem.
If you still get the system rebooting and there is no BSOD then it’s likely that your processor is overheating or your PSU is faulty.
Other possible causes include new device drivers, viruses. You have to check your system for viruses, worms, and Trojans as the first step of the software troubleshooting.
To help figure out whether it’s a software problem (Windows, a driver, a virus, etc.) or a hardware problem, you can try rebooting and entering Setup (CMOS) or booting to MS-DOS from a floppy or to another operating system if you have a dual boot configuration. Wait a while and see if the computer still restarts unexpectedly. If it does, you probably have a hardware or heat problem. If not, it’s probably a problem with the software in Windows.
The random computer rebooting issue is not an easy and straightforward problem to resolve. Be patient and consider logical troubleshooting plan when you address it.
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