Pc crashing

My specs Msi a320m a pro Powercolor red devil rx570 4gb Skihotar 2666mhz 8gb Ryzen 3 1200 Huntkey gx750pro

Game tested: Beamng drive latest version

Using msi afterburner, with amd adrenaline set as "drivers only" @ stock voltage it crashes even at low graphics settings @ -68 undervolt & -15% power limit Everything runs fine only on ultra settings I also set fps cap to 45fps. Gpu temps are 60-70°C. Cpu temps are around 40-50°C. Updated to latest non-beta bios. I also reinstalled windows. My pc either just black screens, crashes the game and the amd driver crash just pops up or my whole pc comepletely just shuts down but i can hear my gpu and cpu fans still running. Or bsod

I am confident that everything else runs smoothly however, i dont know whether my problem sits on the gpu or power supply as im a fairly new pc builder and i acquired the ryzen 3 1200 and rx570 through my uncle, everything used to be my old online learning pc from the pandemic(used to be an athlon 200ge), and the power supply that i bought myself.