PCI Express
Computer expansion bus standard / From Wikipedia, the free encyclopedia
PCI Express (Peripheral Component Interconnect Express), officially abbreviated as PCIe or PCI-e,[1] is a high-speed serial computer expansion bus standard, designed to replace the older PCI, PCI-X and AGP bus standards. It is the common motherboard interface for personal computers' graphics cards, capture cards, sound cards, hard disk drive host adapters, SSDs, Wi-Fi, and Ethernet hardware connections.[2] PCIe has numerous improvements over the older standards, including higher maximum system bus throughput, lower I/O pin count and smaller physical footprint, better performance scaling for bus devices, a more detailed error detection and reporting mechanism (Advanced Error Reporting, AER),[3] and native hot-swap functionality. More recent revisions of the PCIe standard provide hardware support for I/O virtualization.
Peripheral Component Interconnect Express | |
Year created | 2003; 21 years ago (2003) |
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Created by | |
Supersedes | |
Width in bits | 1 per lane (up to 16 lanes) |
No. of devices | 1 on each endpoint of each connection.[lower-alpha 1] |
Speed | Dual simplex, up to 242 GB/s |
Style | Serial |
Hotplugging interface | Yes (with ExpressCard, OCuLink, CFexpress or U.2) |
External interface | Yes (with OCuLink or PCI Express External Cabling) |
Website | pcisig |
The PCI Express electrical interface is measured by the number of simultaneous lanes.[4] (A lane is a single send/receive line of data, analogous to a "one-lane road" having one lane of traffic in both directions.) The 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.
Format specifications are maintained and developed by the PCI-SIG (PCI Special Interest Group) — a group of more than 900 companies that also maintains the conventional PCI specifications.