Confirmed: PCIe 8.0 will double version 7.0’s speed and reach 256.0 GT/s

A new connector may be on the cards, too

The PCI Special Interest Group (PCI-SIG) has confirmed that version 8.0 of the PCI Express (PCIe) specification will allow up to 256 gigatransfers per second, which equates to up to 1 TB/s bi-directionally in a x16 configuration.

The SIG’s announcement of the spec follows the June completion of the PCIe 7.0 spec, which allows for devices that handle 128 GT/s and up to 512 GBps bi-directionally in an x16 lane configuration.

The SIG also said it will achieve stated goals for latency and forward error correction but didn’t enumerate them. The org will also continue to “emphasize techniques to reduce power”, an entirely understandable endeavor given datacenters’ vast appetite for energy.

Work on the spec will also see PCIe wonks review new connector technology.

If the prospect of new PCIe connectors is concerning – as it could be for those planning future server fleets – immediate panic is unwarranted as the SIG will deliver the version 8.0 spec in 2028 and it will likely take years before products that use it reach the market.

Al Yanes, PCI-SIG president and chairperson, thinks the revised spec will still be relevant whenever products that employ it go on sale.

“With the increasing data throughput required in AI and other applications, there remains a strong demand for high performance. PCIe technology will continue to deliver a cost-effective, high-bandwidth, and low-latency I/O interconnect to meet industry needs,” he said in a canned statement.

PCIe SIG roadmap to version 8.0 - Click to enlarge

The SIG quoted Reece Hayden, Principal Analyst, ABI Research, to support that assertion.

“Data center networks are already preparing to implement PCIe 6.0 technology and are showing great interest in the PCIe 7.0 specification,” Hayden said. “The introduction of the PCIe 8.0 specification further ensures that the industry’s bandwidth requirements will be supported well into the future.”

That may well be the case, but yesterday The Register reported a plan to supplant PCIe with all-optical interconnects, perhaps from 2030 – roughly when PCIe 8.0 devices will debut. ®