Having bios problems with my rx 480 8gb

I've been trying to mod the bios for this card for the past couple weeks and can't seem to get anything working. I've tried copying the 1750 timings into the 2000, copying 1500 timings into 1750/2000, over volting, under volting... nothing seems to work..I've tried all the pre built bioses for these cards and they make it only achieve around 15 mh/s, when stock is 23 mh/s.

At the current bios mod/OC it gets 25 mh/s with 1080 and 2000 respectively.

when I try to boost the memory over 2080 it instantly crashes.

card is a XFX RX 480 8gb

Any suggestions?