GPU in PCIEX4 instead of x16

pciex4 slot   Dan bg3 jaheira home pin slot

1 x Slot PCI Express x16 , integrado no chipset: Compatível com o modo PCIe x4 1 x Slot PCI Express x1 , integrado no chipset:

Informações Técnicas ; Chipset: · Memória: · Gráficos Onboard: ; Áudio: · LAN: · Slots de expansão: ; 1 slot PCI Express x16 , integrado no chipset: · 1 slot slot There are total 5 PCIe slots :2 PCIe x1, PCIe x4, PCIe x8, PCIe x16 Among them we recommend PCIe x4 for 10 GB cards

automebet slot However, the 2nd PCIe x16 slot works at PCIe x4 if two GPU are connected means the primary PCIe x16 slot gets 16 lanes and I still have 4 lanes slot, pcie x1 slot, pcie x4 slot, pcie x8 slot, which pcie slot to use, does it matter which pcie