The PCI SIG, overseer of the PCI Express add-in card standard, has finalised version 2.0 of the base specification. The new released doubles the signalling rate from 2.5Gbps to 5Gbps. The upshot: a x16 connector can transfer data at up to around 16GBps.

PCIe 2.0 remains compatible with PCIe 1.1, until now, the latest version of the specification, so older cards will be able to operate in machines equipped with the new version. Intel is expected to release its first PCIe 2.0 supporting chipsets, members of the 'Bearlake' family, next quarter.

The new specification makes the interconnect more interactive, with link speed now a dynamic that can be continuously adjusted by software. Equally, the link will report back changes in bandwidth to the host. Other tweaks to the protocol make for improved device, slot and interconnect management, the PCI SIG said.

PCIe 2.0 also supports more power-hungry add-in cards, though it's not yet known whether the interconnect will provide sufficient power for today' high-end GPUs, many of which require separate power feeds.

The PCI SIG announced PCIe 2.0 revision 0.9 last autumn. ®