PCIe 6.0 and 7.0 standards hit a roadblock — compliance slowdown could lead to broader delays

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Earlier this week PCI-SIG, the organization responsible for development of PCI Express specifications, held its Developers Conference 2024, where it provided updates on the progress of PCIe 6.0 and PCIe 7.0, noting that while advancements are being made, they are slower than initially expected. As a result, adoption of new technologies could face some delays, reports ComputerBase.

In particular, PCI-SIG is delaying the start of its Compliance Program. Preliminary conformity tests for PCIe 6.0 were set to start back in March, but they are now delayed to the 'second quarter,' which theoretically means that they are about to start. A three months delay does not seem like a big issue as the first PCIe 6.0 platforms are coming to market only later this year. But the problem is that Integrators List of compliant products will only be available in 2025. PCIe 6.0 platforms will have to rely on PCIe 5.0 hardware, or use PCIe 6.0 parts without formal compliance guaranteed by PCI-SIG. 

It gets worse with PCIe 7.0 as the timeline for PCIe 7.0 Compliance Program has also shifted, with conformity tests postponed to 2028 instead of the previously announced 2027. Development of PCIe 7.0 has reached draft 0.5, with the final version 1.0 anticipated in 2025. This version aims to deliver a data transfer rate of 16 GB/s per lane, with a maximum configuration offering 256 GB/s. Dual-simplex operation could achieve rates up to 512 GB/s, doubling the 256 GB/s of PCIe 6.0. However, without ability to ensure compatibility between hosts and devices until 2028, PCIe 7.0 will not really take off until later this decade. 

PCI-SIG

(Image credit: PCI-SIG)

In August 2023, PCI-SIG launched a workgroup to solicit industry input on developing optical interconnects for PCIe. This Optical Workgroup is designed to be technology-agnostic, accommodating a variety of optical technologies while potentially creating specific form factors for PCIe solutions. These form factors could include pluggable optical transceivers, on-board optics, co-packaged optics, and optical I/O. 

At the Developers Conference PCI-SIG provided an update on its optical initiatives. The group is currently working on updating the logical and electrical layers of the PCIe 6.0 specification to integrate new optical standards. A significant update, known as the Engineering Change Request (ECN), is expected to be completed by December 2024, enhancing the existing electrical standards without replacing them. Additionally, the workgroup has begun efforts on the optical PCIe standardization for the PCIe 7.0 specification and its release target is set for 2025.

Anton Shilov
Contributing Writer

Anton Shilov is a contributing writer at Tom’s Hardware. Over the past couple of decades, he has covered everything from CPUs and GPUs to supercomputers and from modern process technologies and latest fab tools to high-tech industry trends.