Editing PCI-X (section)

{{Short description|Computer bus and expansion card standard}}
{{distinguish|text=[[PCI Express]] (PCI-E or PCIe)}}
{{redirect|PCIX|the PC Unix port|Interactive Systems Corporation#PC/IX}}
{{Infobox Computer Hardware Bus
|name=PCI-X
|fullname=PCI Local Bus
|image=File:ZRAID at PCI-X at FSC Primtrgy TX200 S2.JPG
|caption=PCI-X motherboard, with one card installed.
|invent-date={{Start date and age|1998}}
|invent-name=[[IBM]], [[Hewlett-Packard|HP]], and [[Compaq]]
|super-date=2004
|super-name=[[PCI Express]]
|width=64
|numdev=
|speed=Half-duplex<ref>{{Cite web|title=PCIe (Peripheral Component Interconnect Express) {{!}} On the Motherboard {{!}} Pearson IT Certification|url=https://www.pearsonitcertification.com/articles/article.aspx?p=2731934&seqNum=24|access-date=2020-09-25|website=www.pearsonitcertification.com}}</ref>
266–4266&nbsp;MB/s
|hotplug=Optional
|style=p
}}

'''PCI-X''', short for '''Peripheral Component Interconnect eXtended''', is a [[computer bus]] and [[expansion card]] standard that enhances the 32-bit [[Conventional PCI|PCI]] [[local bus]] for higher [[Bandwidth (computing)|bandwidth]] demanded mostly by [[Server (computing)|servers]] and [[workstations]]. It uses a modified protocol to support higher [[Clock rate|clock speed]]s (up to 133&nbsp;MHz), but is otherwise similar in electrical implementation. PCI-X 2.0 added speeds up to 533&nbsp;MHz,{{r|PCIX2.0|p=23}} with a reduction in electrical signal levels.

The slot is physically a 3.3&nbsp;V PCI slot, with the same size, location and pin assignments. The electrical specifications are compatible, but stricter. However, while most conventional PCI slots are the 85&nbsp;mm long 32-bit version, most PCI-X devices use the 130&nbsp;mm long 64-bit slot, to the point that 64-bit PCI connectors and PCI-X support are seen as synonymous.

PCI-X is specified for both [[32-bit computing|32-]] and [[64-bit computing|64-bit]] PCI connectors,{{r|PCIX1.0a|p=14}} and PCI-X 2.0 added a [[16-bit computing|16-bit]] variant for embedded applications.{{r|PCIX2.0|p=22}}

PCI-X has been replaced in modern designs by the similar-sounding [[PCI Express]] (PCIe),<ref name="Andrews2010">{{cite book|author=Jean Andrews|title=A+ Guide to Managing and Maintaining Your PC|url=https://archive.org/details/labmanualtoaccom07edandr|url-access=registration|year=2010|publisher=Cengage Learning|isbn=978-1-4354-9778-8|page=[https://archive.org/details/labmanualtoaccom07edandr/page/187 187]}}</ref> with a different physical connector and a different electrical design, having one or more [[Serial communication|serial]] lanes instead of a number of slower [[Parallel communication|parallel]] connections.