After modifying 1500-2000+ stripes on my Sapshire Nitro+ RX 580 8GB (Samsung) using PBE or SRBPolaris I try to verify with ATIflash and always get error on BIOS integrity:  

AtiFlash.exe -v 0 bios_modified.rom
0x21/0x40000 bytes verified

   ERROR: 0FL04

Same error also when running -v on "Anoraks_Sapphire RX 580 Nitro(plus) 8GB Samsung Hynix_memshift-1750.rom"

What am I missing?