Specifications
Computer Architecture and Maintenance (G-Scheme-2014)
can operate on both voltages, have two notches. Version 2.1 of the PCI standard
introduced optional 66 Mhz operation.
A server-oriented variant of conventional PCI, called PCI-X (PCI Extended) operated at
higher frequencies, up to 133 Mhz for PCI-X 1.0 and up to 533 Mhz for PCI-X 2.0. An
internal connector for laptop cards, called Mini PCI, was introduced in version 2.2 of
the PCI specification. The PCI bus was also adopted for an external laptop connector
standard—the CardBus.The first PCI specification was developed by Intel, but
subsequent development of the standard became the responsibility of the PCI Special
Interest Group (PCI-SIG).
Conventional PCI and PCI-X are sometimes called parallel PCI in order to distinguish
them technologically from their more recent successor PCI Express, which adopted a
serial, lane-based architecture. Conventional PCI's heyday in the desktop computer
market was approximately the decade 1995-2005. PCI and PCI-X have become obsolete
for most purposes, however, they are still common on modern desktops for the
purposes of backwards compatibility and the low relative cost to produce. Many kinds
of devices previously available on PCI expansion cards are now commonly integrated
onto motherboards or available serial bus and PCI Express versions.
PCI Express(PCIe) (Peripheral Component Interconnect Express), officially
abbreviated as PCIe, is a high-speed serial computer expansion bus standard designed
to replace the older PCI, PCI-X, and AGP bus standards. PCIe has numerous
improvements over the aforementioned bus 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)), and native hot-plug functionality.
More recent revisions of the PCIe standard support hardware I/O virtualization.
Connector
At least 3 or 4 PCI connectors are generally present on motherboards and can generally
be recognised by their standardized white color.
The PCI interface exists in 32 bits with a 124-pin connector, or in 64 bits with a 188-pin
connector. There are also two signalling voltage levels:
• 3.3V, for laptop computers
• 5V, for desktop computers
Prepared By – Prof. Manoj.kavedia (9860174297 – 9324258878 ) (www.kavediasir.yolasite.com)
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