Intended to replace PCI, PCI-SIG introduced the
PCI Express standard, which is available now in a range of host systems.
[more]Unlike PCI, PCI Express (
PCIe) is a very high performance serial bus standard currently capable of transfers of up to 250MB/s per lane in a single direction. With the ability to transfer data in both directions (full-duplex) and utilize a maximum of 32 lanes per device, PCIe is theoretically capable of combined transfers of 16Gb/s.
PCI Express' strongest suit is that is is based on existing PCI protocols. With changes in the physical layer only, new systems can utilize PCIe without changes to the underlying OS or driver software for devices. This factor has sped up adoption of
PCI Express over other technologies as vendors can leverage their existing investments in PCI compatible hardware and software without major changes.
PCIe's speed and flexibility allow for exciting applications such as full throughput SATA RAID and FireWire 800 host adapters that underperformed under 32-bit/33MHz PCI. PCIe has also eliminated the need for a separate AGP bus, as multi-lane PCIe provides similar throughput
