Specifications

PCI-SIG specifications define standards driving the industry-wide compatibility of peripheral component interconnects. Members regularly review them, providing commentary and change requests when necessary. These requests are considered by technical workgroups and applied as appropriate, resulting in collaboratively devised specifications benefiting millions of platforms and add-in devices.

Engineering Change Request Process
PCI-SIG members may submit requests to change specifications here. The Engineering Change Request process and form can be found here

Purchasing Specifications
PCI-SIG members may access specifications online, at no cost, using the Specification Library. Members may filter their search by technology type, revision, and the type of document. Select the appropriate filters and then select the Filter button to initiate your search. Alternatively, members may purchase a hard copy of the specifications, at a reduced member rate, here.

Non-members who are interested in purchasing specifications may submit their order here.

PCI Code & ID Assignment Specifications
The PCI Code & ID Assignment Specifications are accessible to non-members without charge here. PCI-SIG members can download these specifications directly from the Specifications Library below.

Specifications Library

Technology: PCI Express
Specification Title Spec Rev Document Type Release Date
PCI Express Base Specification Revision 5.0, Version 1.0
This specification describes the PCI Express archite...view more This specification describes the PCI Express architecture, interconnect attributes, fabric management, and the programming interface required to design and build systems and peripherals that are compliant with the PCI Express Specification. show less
5.x Specification
PCI Express Base Specification Revision 5.0, Version 1.0 (Change Bar Versions)
There are four informative ...view more There are four informative "changebar" versions of the PCI Express Base 5.0 Specification comparing Base 5.0/1.0 to Base 5.0/0.9 and comparing Base 4.0 and Base 5.0. HTML and PDF versions are provided. Both versions are derived from common source material but have different characteristics, and readers may wish to reference both. These documents are non-normative - the NCB PCI Express Base Specification Revision 5.0, Version 1.0 (NCB-PCI_Express_Base_5.0r1.0-2019-05-22.pdf) is the normative version of this specification. show less
5.x Specification
PCI Express Card Electromechanical Specification Revision 5.0
This Card Electromechanical (CEM) specification is a...view more This Card Electromechanical (CEM) specification is a companion for the PCI Express® Base Specification, Revision 5.0. Its primary focus is the implementation of an evolutionary strategy with earlier PCI™ desktop/server mechanical and electrical specifications. show less
5.x Specification
PCI Express Card Electromechanical Specification Revision 5.0 (Change Bar)
This Card Electromechanical (CEM) specification is a...view more This Card Electromechanical (CEM) specification is a companion for the PCI Express® Base Specification, Revision 5.0. Its primary focus is the implementation of an evolutionary strategy with earlier PCI™ desktop/server mechanical and electrical specifications. show less
5.x Specification
PCI Express Architecture PHY Test Specification, Revision 5.0, Version 1.0
This document provides test descriptions for PCI Exp...view more This document provides test descriptions for PCI Express electrical testing. It is relevant for anyone building Add-in Cards or system boards to the PCI Express Card Electromechanical Specification 5.0. show less
5.x Specification
PCI Express Architecture Configuration Space Test Specification Revision 5.0, Version 1.0
This document primarily covers PCI Express testing o...view more This document primarily covers PCI Express testing of all defined Device Types and RCRBs for the standard Configuration Space mechanisms, registers, and features. show less
5.x Specification
PCI Express Architecture Link Layer and Transaction Layer Test Specification Revision 5.0, Version 1.0
This test specification primarily covers testing of ...view more This test specification primarily covers testing of PCI Express® Device and Port types for compliance with the link layer and transaction layer requirements of the PCI Express Base Specification. show less
5.x Specification
PCI Express M.2® Specification Revision 5.0, Version 1.0
The M.2 form factor is intended for Mobile Adapters....view more The M.2 form factor is intended for Mobile Adapters. The M.2 is a natural transition from the Mini Card and Half-Mini Card (refer to the PCI Express Mini CEM Specification) to a smaller form factor in both size and volume. The M.2 is a family of form factors that enables expansion, contraction, and higher integration of functions onto a single form factor module solution. show less
5.x Specification
PCI Express Card Electromechanical Specification Revision 5.1, Version 1.0 CB
This Card Electromechanical (CEM) specification is a...view more This Card Electromechanical (CEM) specification is a companion for the PCI Express® Base Specification, Revision 5.0. Its primary focus is the implementation of an evolutionary strategy with earlier PCI™ desktop/server mechanical and electrical specifications. show less
5.x Specification
PCI Express Card Electromechanical Specification Revision 5.1, Version 1.0 NCB
This Card Electromechanical (CEM) specification is a...view more This Card Electromechanical (CEM) specification is a companion for the PCI Express® Base Specification, Revision 5.0. Its primary focus is the implementation of an evolutionary strategy with earlier PCI™ desktop/server mechanical and electrical specifications. show less
5.x Specification
PCI Express Retimer Test Specification Revision 5.0
This test specification is intended to confirm if a ...view more This test specification is intended to confirm if a stand-alone Retimer is compliant to the PCIe Base Specification. This test specification is not intended to test Retimers based only on the Extension Devices ECN to the PCI Express Base Specification, Revision 3.x. This test specification only covers stand-alone Retimers in common clock mode, and is not intended to test Retimers integrated onto a platform or an add-in card. show less
5.x Specification
PCI Express SFF-8639 Module (U.2) Specification Revision 5.0
The focus of this specification is on PCI Express® (...view more The focus of this specification is on PCI Express® (PCIe®) solutions utilizing the SFF-8639 (also known as U.2) connector interface. Form factors include, but are not limited to, those described in the SFF-8201 Form Factor Drive Dimensions Specification. Other form factors, such as PCI Express Card Electromechanical are documented in other independent specifications. show less
5.x Specification
PCI Express Architecture PHY Test Specification Revision 5.1
This document provides test descriptions for PCI Exp...view more This document provides test descriptions for PCI Express electrical testing. It is relevant for anyone building Add-in Cards or system boards to the PCI Express Card Electromechanical Specification 5.0. This specification does not describe the full set of PCI Express tests and assertions for these devices. show less
5.x Specification