black screen boot Black screen on boot

[Ccem]

I got a new set up, after a day I get black screen on boot and the bios don't show up please help.

i7 7700k (new)
Msi z270 carbon itx (new) replaced 2nd time new
CPU cooler: cooler master v8 (old)
G skill trident z. 2x 8 GB 2400mhz ( new )
Palit gtx 1070 dual ( used new)
Ssd: Samsung evo 120gb w 10 (old)
750 w power (old)
Phanteks enthoo evolve itx ( new)

I am 100% shure itx not the gpu because I changed it.
The setup was doing fine, until I played a game and then the PC reboot and turned black screen.

Everything lights up and works but the monitor can't get any source. 

Also the server indicator on case (that one with the blinking light) does not blink anymore. 

This happened with another case so it must be the mobo, this is the 2nd same mobo because I returned the first one with same problem. So j think it's the mobo.

I've disassembly the pc many times correctly and I can't find the problem. This problem happened this morning and suddenly when I played with the dvi cable it came randomly on. So 1÷ chance that it may turn on. Sorry for bad English I will reply any questions.

[MattL1]

Not sure if this will help but i would try rebooting your monitor. Occasionally on my VG28QE I wont be receiving signal from my PC but a monitor reboot usually fixes it.

[Ccem]

1 hour ago, MattL1 said:

Not sure if this will help but i would try rebooting your monitor. Occasionally on my VG28QE I wont be receiving signal from my PC but a monitor reboot usually fixes it.

I've tried that, wont help unfortunately.