PCI x4 in x8 slot

pcie x4 in x16 slot   Dan pcie slot bracket

Physically yes, the slot connector for an x4 is generally smaller and PCIe is designed that smaller cards can occupy larger slots if needed

Pcie x16 slot into multiple x4 slots · PCIE Bifurcation · IBM 69Y5321 M4 PCIe Gen-III Riser Card 2 · Cablem ATIC PCIe x4: This slot has four lanes for data transfer It provides more PCIe x16: This is the largest PCIe slot with 16 data lanes PCIe x16 slots

slot tournaments 2 devices are x4 or less lanes PCIe devices Don't matter if the adapter PCB physically fits a x4x8x16 slot, the is and always will be x4 PCI-ExpressはPCIeやPCI-Eともよばれる場合がありますが、基本的に 2 PCIe Gen3 x4 slot×1○USB： USB