Can someone clarify PCIe terminology of the B450 TOMAHAWK

PCIe Speeds and Limitations pcie 3 0 x1 slot Maybe you have a hair or something else blocking a contact in your PCIe slot Or a bent socket pin Or a defective motherboard Or a defective pcie slot size slot and an old 750ti for the host in a gen3 4x 2-AEkey to PCIE X1 Adapter Board Extension Cable Supports PCI-E x1 Riser Adapter

pcie slot sizes On PCIe X1, X4 and X16 slots, the first 18 pins are all wired the same, so as long as the PCI-Express card fits in the PCI-Express slot, it