Wednesday, July 05, 2006

PCI-X standards

PCI-X (Peripheral Component Interconnect Extended) is a computer bus technology that
increases the speed that data can move within a computer up to 133 MHz. The technology was developed jointly by IBM, HP, and Compaq. PCI-X doubles the speed and amount of data exchanged between the computer processor and peripheral devices. With the current PCI design, one 64-bit bus runs at 66 MHz. Additional buses move 32 bits at 66 MHz or 64 bits at 33 MHz. The maximum data rate between the processor and peripherals using the traditional PCI design is 532 MB per second. With PCI-X, one 64-bit bus runs at 133 MHz, allowing for a data exchange of 1.06 GB per second (133X8bytes=1.064Gbytes). PCI-X is backwards-compatible. You can use both PCI and PCI-X cards on the same bus but the bus speed will run at the speed of the slowest card. Fault torerance is built in to PCI-X.

PCI-X 2.0

PCI-X 2.0 is a higher speed version of the PCI X ( more specifically PCI-X 66 and PCI-X 133) standard. PCI X 2.0 provides for two new speed grades: PCI-X 266 and PCI-X 533, offering up to 4.3 gigabytes per second of bandwidth. PCI-X 2.0 offers enhanced system reliability. ECC support has been added, providing automatic single-bit error recovery and double-bit error detection.

PCI-X 2.0 is built upon the same architecture, protocols, signals, and connector as traditional PCI. Migration to PCI-X 266 and PCI-X 533 is simplified by retaining hardware and software compatibility with previous generations of PCI and PCI-X. As a result, new designs can immediately connect with hundreds of PCI and PCI-X products that are currently available.

Summary of PCI-X 2.0 Features

  • Up to 32 times faster than traditional PCI bus speed
  • Doubles and Quadruples PCI-X bandwidth.
  • Full hardware and software backward compatibility.
  • Uses the same form factor, pin-outs, connector, bus widths, and protocols.
  • Enables 10Gb Ethernet, 10Gb Fibre Channel, InfiniBand™ Architecture, and
    other IO technologies.
  • Full RAS support including ECC.