1. Try connecting to different video outputs on the PC. Sometimes a change in driver can cause the video to be sent:
To a different Adapter: from integrated graphics to a discrete card or vice versa.
To a different output: from HDMI to DVI, DisplayPort to VGA, or any other combination.
2. Try to boot into Safe Mode with Networking or Enable low-resolution video.
Advanced boot options, Safe Mode with Networking, or Low Resolution Video.
http://windows.microsoft.com/en-us/windows-10/change-startup-settings-in-windows-10#v1h=tab01