weird gpu behavior

[tenchu117]

i know its not overclocking related but i figured overclockers might have better understanding of a peculiar problem regarding gpus so here we go:

i have a graphics card rx 580 sapphire pulse 4gb that wont display anything unless u plug it on a specific hdmi slot. it will not work on dvi port, other hdmi port (havent tried display port yet cuz i dont have any dp cables).

here is another curve ball, it wont run above 300 mhz both clock spd and memory speed. i tried a few games it will either post out a memory error or just straight up crash.

i have tried to reflash the bios from gpuz, i have tried up to 3 monitor, 5 varied hdmi/dvi cables. ive reinstalled the driver, tried on 3 diff motherboards (amd/intel eufi n bios capable)

any replies is appreciated ty in advance.