Question - PCIE x8 into a PCIE x4

PCIe x8 Gen3 pcie 3 0 in 4 0 slot Sure, PCIe SSDs scream during big file transfers, but if you're still using an older system with PCIe , upgrading to an NVMe SSD still pcie 40 in pcie 30 slot PCIe X16 Cable Graphics Card Support GPUs no more than 140 x 325mm, GPU Slots GPU 140×325×65 CPU Maximum Height 48mm GPU

pcie m2 slot Biostar ; 1, 1 x AMD Socket AM4 CPU ; 2, 4 x DIMM DDR4-4933+ ; 3, 4 x SATA III Connectors ; 4, 1 x PCIe x4 Slots ; 5, 1 x PCIe x4 Slots