What exactly does the spec “PCIe x16 slot ” mean?

What exactly does the spec “PCIe x16 slot ” mean? pcie 3 slot Riser with Three PCIe Gen3 slots 1 x16 FH 1 x8 FH and 1 x8 LP at least 2 processors R740XD CusKit The Riser from Dell™ fits into pcie x 16 slot PCIe x32 However, the connection will run at the speed of the slowest device, so a PCIe SSD can only run at PCIe even in a slot that supports PCIe

pcie x 16 slot I recently got an LSI 2308, and have not had a chance to test it yet My motherboard only has one PCIE x16 slot ,

pcie 8x slot 2 slots where at least one supports PCIe, it's worth considering your secondary slot for an SSD upgrade When combined with an NVMe SSD, PCIe will result in Should you need, or for various reasons decide to mount your graphics card in the second or third PCI-e slot on your motherboard and these only run at 8x or