PCI Express

PCI Express, also read as PCIe or PCI-e, is one of the high-speed serial computer expansion bus standard. It is the common motherboard interface for personal computers' graphics cards, hard disk drive host adapters, SSDs, Wi-Fi and Ethernet hardware connections. Comparing with the rest older standards, it has not only higher maximum system bus throughput, lower I/O pin count, smaller physical footprint, better performance scaling for bus devices, but also a more detailed error detection and reporting mechanism.

The PCI Express electrical interface is also used in a variety of other standards — most notably the laptop expansion card interface called ExpressCard. It is also used in the storage interfaces of SATA Express, U.2 (SFF-8639) and M.2.