Question rx 5700 not outputting image

[nenadilievski72]

i got brand new system few days ago with rx 5700. it was working fine and i tried flashing rx 5700 xt bios on it so i brcked it but shortly after recovered to old bios using my old gpu. after that the card was running and stable (i played forza horizon 4 on 4k). the next day when i turned on thr pc absolutely no signal.
tried resetting the gpu and using different slot with no results.
what could be my issue here and what should i do?

 

[rgd1101]

full system spec? include make and model of the psu

 

[nenadilievski72]

full system spec? include make and model of the psu

i dont exactly know becouse its friends pc but its a Corsair 750w unit. ryzen 5 3rd gen and some nice mobo not shure what it is.