|Go to "Control Panel > Power Options" and make sure the screen setting time out is not set too low. |
Otherwise try an external monitor on it and let us know if that does the same.
Sometimes the cable between the laptop and the screen (or its connectors at either end) can give trouble. When it goes off try slowly moving the lid down to nearly closed and if it comes back most likely it is cable wear where it hinges.
Always pop back and let us know the outcome - thanks