What is the difference between 64-bit PCI slot and

pci slotPCIe slots come in a variety of physically different sizes referred to by the maximum lane count they support, ie. x1, x2, x4, x8, x16, and x32. A PCIe card will fit into a slot of its size or bger,PCIe is different from PCI. PCIe is faster and it can be used to connect devices like graphics card that PCI can't support nowadays.