Asrock/OEM cannot support more then 3GPU

Hi everyone, frist time on a forum =D
I jus begin mining ETH, and my Asrock/OEM cannot support more then 3 GPU, but it have 4 PCI-E 16X et 2 1x so its seem not logical.
I try everything i can in the BIOS whitout result, just boot on a blacksreen whit a little < - > flashing on top left corner. Unfortunaly the MOBO is not supported by Asrock so no bios update.

Any ideas ? Thx =) Or any motherboard i can buy instead ? 150$ CAD Budget =) I think about the MSI Z370 GAMING PLUS LGA 1151

Bios - L0.01
CPU - G4930 Intel
16 GB of Ram

#solve need more PCI lane.