Hey,
As per my understanding of your problem your computer restarts automatically. This problem arises due to malfunctioning shell-extensions, corruption of the system files, incorrect power settings, and so on. Since your question lacks detailed information about your machine I’m hereby providing complete troubleshooting guide.
[B][U]Diagnose your Memory[/U][/B]
- Press Windows Key + X.
- Click Search.
- Type “Memory” in the Search Box.
- Click the Settings icon.
- Open “Diagnose your computer’s memory problems”.
- Click “Restart now and check for problems” button. The computer will be automatically restarted and it’ll conduct several memory tests.
[B][U]Run the System File Checker[/U][/B]
- Insert Windows 8.1/ 8 installation disc.
- Press Windows Key + X.
- Click “Command Prompt (Admin)”.
- Type the following command:
sfc /scannow - Press ENTER.
[B][U]Reset Power Settings[/U][/B]
- Press Windows Key + X.
- Click Power Options.
- Click “Change plan settings” link ahead of the selected active plan.
- Click “Restore default settings for this plan” link.
- Click “Save changes” button.
For more troubleshooting guidelines please [URL=‘https://www.youtube.com/watch?v=T4rWDGVCxMU’]watch this video[/URL].