I also had this problem under windows 7 on the same machine and it persisted through an upgrade to Win10. The monitor is set to turn off in 10 minutes, although the time doesnt matter, and sleep is set to never yet the monitor never turns off. I have tried powercfg /requests which comes up with nothing. The NIC is set to be turned off for power saving and the only other devices are a mouse, keyboard and webcam.