Knowing PCIe Slots: A Complete Guide PCIe, or peripheral component interconnect express, is a high-speed interface standard that is now the foundation of contemporary computer architecture. Sreact slotsince their introduction in the early 2000s, PCIe slots have completely changed how parts of a computer system interact with one another, enabling faster data transfer rates & better system performance. Each device connected to the motherboard has its own dedicated bandwidth thanks to PCIe's point-to-point architecture, which sets it apart from its predecessors like PCI and AGP.