Sometimes for no known reason your PC instantly reboots and perhaps is doing it frequently.
There a many reasons for a PC to reboot unexpectedly, so any significant reasons will be listed below.
The startup procedure can overlook a problem RAM stick and yet have Windows restart at any moment when the relevant area of memory is accessed.
Remedy 1 - Set the bootup bios to slow memory checking
- Go into the startup BIOS menu and set the bootup to NOT use a quick boot.
- Restart the PC and the memory count should be slower.
- See if the bootup reports a RAM fault.
- If so, try each memory stick on its own to see if the report happens again until you know which stick of memory is faulty.
- Throw the faulty stick of memory in the bin and replace with equivalent memory stick
Remedy 2 - Use a bootable CD to check the RAM memory
- Start the PC with a bootable memory checking CD inserted (ie the free Barts Bootup CD)
- Let the software examine the memory for faults.
- Replace any memory stick that the program reports as faulty.
Normal Windows running files are corrupt or missing causing an instant reboot.
Remedy 1 Checking Windows core files are not corrupt
- Start Windows in Normal or Safe Mode (by tapping [F8] when the PC first starts)
- Insert the Windows CD and cancel the dialog that shows up
- At the desktop click Start and then Run
- Type sfc /scannow in the Run box and press [Enter]
- SFC will attempt to repair or replace any corrupted Windows file.
- Restart Windows and random reboots may not occur any more
Remedy 2 Checking for Virus / Spyware
- Run a virus and spyware checking program (see virus/spyware section of web site)
- Follow the software guidelines if problems are found and random reboots may not occur any more
Remedy 3 Reinstall the Windows System from the correct Windows CD
- Start the PC with the Windows CD inserted
- Let the drivers load up and select install Windows and choose the hard drive and location of the existing installed Windows.
- Confirm you want to overwrite the existing installation BUT make sure you select to REINSTALL and NOT a new INSTALL so that your existing Windows will be technically repaired and not new.
- After a REINSTALLATION of Windows you may have solved what was causing the random reboots.