Why does my laptop screen keep turning black?

I own a Lenovo ideapad with an NVIDIA Geforce GT 650M graphics card. Windows 8 is the OS installed. Everything worked fine on the laptop until I updated to Windows 8.1.

If I let the laptop sit for more than one minute, the screen will turn black. The backlight stays on, so the screen is not turning completely off. Any key press or mouse movement will "wake" the screen from this state.

I have checked several things to try and resolve the issue. I have updated my graphics card drivers to the latest versions. I have restarted my PC a few times. I have observed this behavior while it is plugged into an outlet or unplugged and running off the battery.

I have also looked into the power settings for my PC. The screen is not set to turn off until 15 minutes and the laptop isn't supposed to go to sleep until 30. Adaptive brightness is not enabled.

Same thing happened to me. I took it to get repaired and it turned out that my hard drive was messed up! I recommend taking it to a technician. Right i'm dealing with something similar, my tablet won't turn on etc.