Method #1:
It may be that your Windows XP OS has contracted a virus. Please refer to the following website for additional information:
http://www.microsoft.com/security/
Also, you may want to make sure that you are up to date as far as Windows Updates are concerned as well as having anti-virus software installed with updated definitions. At the very minimum, if you do not have anti-virus software is to enable the Internet Connection Firewall. All of this information can be found at the above website.
Method #2:
Boot from the installation CD, and when given the option, select Install, let setup scan for (and discover) a previous installation of XP. You are then given the option to either install a fresh copy or repair, select repair.
Method #3:
If the restarts are more of a random nature and you are able to get to your desktop, then try the following:
The problem could be Spyware/Adware related. I recommend using a quality adware scanner to see if this solves the problem. Use one of the following 3 or even all three if need be.
* Adaware 6.0
* Spybot S&D
* CWShredder
All of these scanners can be downloaded at the Virus Information page for free.
Method #4:
If the restarts are more of a random nature and you are able to get to your desktop, then try the following:
Try disabling the "Automatic Restart feature. Once you do this, the result will be a blue screen with an error message that should basically tell you what is going wrong with your system. To disable this feature:
Right click on my computer, select properties then advanced tab. Under "Startup and Recovery", select Settings. Then in "System Failure", uncheck
'Automatically Restart'.
Method #5:
If this problem started because of an upgrade, it could be that you are having driver conflicts. The first driver I would replace is the Video, then the Sound Card and then the Modem.
Method #6:
This problem has been known to be cause from Software conflicts. Try turning off all programs in MSCONFIG.
Go to: Start> Run> type in: msconfig [Enter] Select the Startup tab, then uncheck all of the programs listed in the resulting menu. Reboot your system. If the restarting problem is gone, turn each of the programs back on one at a time until the conflicting program is isolated.
Method #7:
It could be that your CPU is getting hot. If you feel comfortable getting inside your computer, make sure that it is somewhat dust free, while making sure that your fans are functioning properly. There are devices that you can install to monitor the temperature of your CPU.