This may help resolve the issue:
https
/forums.lenovo.com/t5/Gaming-Laptops/y520-and-oculus-vr-via-hdmi/m-p/3688546#M7007
Once you have selected the High Performance in the NVIDIA panel, go to Power setting in Control Panel. Go into Advanced and turn off "USB Selective suspend setting".
Restart the machine.
Here is a potential discussion on this issue -
https
/forums.oculus.com/community/discussion/36284/rift-hdmi-is-not-being-detected-on-win10-x64
Some people have fixed it by -
1) Installing an older version of the drivers. (You can try installing the ones that are on Lenovo website)
2) Using an HDMI to DVI adapter.
3) There is a post from RoadToNothing which details on how he solved for himself.
4) Some people also reseated their HDMI to solve it.
https

/support.oculus.com/help/oculus/1114691701909297