Question Asrock B450m-Hdv blank screen new build

[Gav b]

Asrock B450m-Hdv blank screen new build every thing else seams to be working fans, hdds but nothing on screen

 

[rgd1101]

full system spec? include make and model of the psu

 

[Gav b]

Mb as rock b450m hdv
Amd ryzen 5 2600
Cit atv 500r psu
Corsair ddr4 8gb 3000mhz
No gpu as yet was gonna use onbourd for a few days

 

[rgd1101]

ryzen don't have igpu, need a gpu to display