PCI Express 3.0 to push 8GT/s
PCI-SIG has announced
that the next, next-gen PCI Express 3.0 spec will offer a maximum bit rate of 8GT/s—double that of PCI Express 2.0. Interestingly, PCI-SIG considered pushing a 10GT/s maximum bit rate, but settled on a slightly slower speed, in part to maintain backwards compatibility.
“Experts in the PCIe Electrical Workgroup analyzed both 10GT/s and 8GT/s as target bit rates for the next generation of PCIe architecture, and after careful consideration of several factors, including power, implementation complexity and silicon area, recommended 8GT/s,” said Al Yanes, PCI-SIG chairman. “This allows us to satisfy the next generation performance requirements for all existing PCIe applications while maintaining backward compatibility, and at the same time broadening the adoption of this pervasive technology into new and emerging applications and usage models.”
Along with additional bandwidth, PCI Express 3.0 adds support for "transmitter and receiver equalization, PLL improvements, clock data recovery, and channel enhancements for currently supported topologies." Don't expect to see PCIe 3.0 anytime soon, though. Core logic chipsets with PCI Express 2.0 support aren't due until the fall, and it could be 2010 before products built for PCIe 3.0 become available. Thanks to Xbit Labs
for the tip.