How is possible Edit Bios from Rx580 sp 8gb Micron Reducing for 4gb?

Hello My card is broken cant got Video and on Windows got error 43.My A0 and A1 modules have problems or may be GPU controler fault.The card have all tensions well i wish know if possible ISOLATE 2 BANKS OF MEMORY in GPU for work with C0 C1 and D0 D1.If possible anybody can help me please.The Model is a Soyo(xfx clone with rx470 chip) rx 580 sp 8gb Micron

Obs: I dont have any of this modules and i think problem can be exist on memory controller gpu its internal.I thnk betrer isolate banks reducing from 8gb to 4gb