Input signal not found

[MsPersistent80]

When I turn on the PC a little box pops up and says input signal not found  as well as it also says in that little box HDMI check the video cable and the video stores display going to sleep. 

[WAWood]

This is almost certainly an indication of failing video hardware -- either the monitor or the video chip/card or both.

To check for the monitor, you need to do both of the following:
1) Connect the monitor to another PC
2) Connect a different monitor to this PC

If 1) works OK, then the monitor is good; if it fails, then at least the monitor is bad -- but the video chip/card may also be bad.

If 2) works, the video chip/card is OK.

If you have a video card, then the card is failing and needs to be replaced. But if you have Integrated Video, then you are using the chips oldered to the motherboard and those are not replaceable.