Starting two weeks ago, on my Lenovo IdeaPad Y500, about 1 in 10 times, the laptop's built-in LCD screen comes on normally when I power on or restart the laptop. The other 9 times, the screen remains completely black, no Lenovo logo, no Windows signon screen, no faint grey glow. I have no problems waking the computer from sleep; the screen comes on every time. Once the screen is on, it stays on and has no further problems until I shut down or restart.
The computer is not connected to an external display or docking station. I did not make any changes to hardware or software before this problem started. I have the most recent version of Windows (8.1) and the most recent version of the NVIDIA display drivers (331.58). I've also tried older drivers (307.64) with no success.
I have performed several troubleshooting steps:
1. I placed a sound file in my Windows startup folder. When I power on the computer, blindly enter my password when the screen is black, and wait a few seconds, I hear the sound, so Windows is starting up normally even when the screen is blank.
2. When the screen is black, about 1 out of 20 times, closing and opening the lid causes the screen to come on normally.
3. When the screen is black, about 19 out of 20 times, closing and opening the lid causes the screen to go from black to a faint grey glow, but nothing displays. Pressing FN-F2 repeatedly toggles the screen from black to grey and back to black.
4. If I connect an external display via the HDMI port when the laptop screen is working, the external display also works fine, and all 4 options work when pressing FN-F3.
5. If I connect an external display via the HDMI port when the laptop screen is not working and press FN-F3...If I choose "PC screen only," "Duplicate," or "Extend," the laptop display is blank and the external display works. If I choose "Second screen only," both displays are blank.
6. Removing the second video card from the UltraBay does not change the behavior.
Although I'd doubt this is related, around the same time the screen problem began occurring, I began having sporadic problems with both the trackpad and USB mouse where they seem to be miscalibrated. The position of the cursor on the screen is about an inch away from where the text appears if you begin typing.
Any help or ideas would be appreciated.