Question New pc, black screen, boot led on

[Ares6996]

Hello, i just finished my new pc with these parts:
Msi B450-A Pro Max
Ryzen 7 2700x+stock cooler
Gigabyte Gt 1030 (from my old pc)
m2 ssd
CoolerMaster Mwe bronze v2 650w
After a few cable issues it turned on, the gpu,cpu cooler,psu,systemfan works. But i got black screen and the last led on mobo is on (boot led)
i dont have windows installed.
What i have to do somebody please help.
Should I remove the mobo battery and place it back?

 

[rgd1101]

monitor connect to the gpu?
what connection are you using? dvi/dp/hdmi?

 

[Ares6996]

monitor connect to the gpu?
what connection are you using? dvi/dp/hdmi?

yes its connected vith hdmi-vga converter, the monitor worked with my old system.