List of fully supported mb:
ASRock H81 PRO BTC (6x gpu) Link
BIOSTAR TB85 (6x gpu) Link
MSI Z270-A PRO (6x gpu: 7x if you use 1x m2 adapter) Link
GIGABYTE GA-B250M-Gaming 3 (4x gpu) Link
BIOSTAR TB250-BTC (6x gpu) Link
ASUS Z270-F GAMING (7x gpu: 9x if you use 2x m2 adapters)  Link
MSI Z170A GAMING M5 (7x gpu) Link
ASUS PRIME Z270-A (7x gpu: 9x if you use 2x m2 adapters) Link
GIGABYTE GA-Z270P-D3 (6x gpu) Link
ASUS PRIME H270-PLUS (6x gpu: 8x if you use 2x m2 adapters) Link

Just burn the iso on a stick and give it a try.
Do a bios update if available and try again in win/linux