Screen Goes Black Randomly

[Arnager]

I have recently build a pc with specs given below but there is an issue i am facing ever since , randomly when i doing some thing browsing, gaming etc. on my pc the screen goes black and a sound of device diconnection comes in . But after a restart the screen comes back but with display drivers disabled and  the drivers shifted to Microsoft Basic Display driver.After that i have to manually enable the drivers and update the drivers to vega drivers eveytime this happens .plz help!!!

SPECS - RYZEN 3400g with vega 11 graphics 
               16gb xpg ram
                Asrock A320 m HDV 4.0
                450W COOLER MASTER PSU
               Integrated Graphics