The PCI Special Interest Group is working on the PCI Express 4.0 standard, which would double the maximum transfer rates to 16 gigatransfers per second. PCIe 4.0 would be the last standard based on copper, with a move to optical board superseding it. Detailed requirements are still up in the air, but the speed targets are thought to need new chips to properly feed boards longer than 10-12 inches.
