You realise yourself have bought the China exclusive RX 580 with only 2048 shaders ? Actually GPU-Z is correct also, it is equivalent to an RX 470.
RX580 for all other market have 2304 shaders. That is why when you go flash an RX580 BIOS into it, you get error.
Maybe try flashing the correct BIOS again. Remember yours is a 2048SP version, not the 2304SP ones .

But I will say, most likely your VRAM is shot.


If everything else don't work, maybe you wanna try if you really got nothing to lose anymore


This post has been edited by k!nex: Feb 24 2021, 01:31 AM