PCIe 8.0 Confirmation: New Version Offers Double Speed Over 7.0, Reaching 256 GB/s
PCI Express Version 8.0 Announced: Focus on Copper Interconnects for Now
The PCI Special Interest Group (PCI-SIG) has announced the upcoming release of PCI Express (PCIe) version 8.0, expected around 2028. Despite rumours of all-optical interconnects as a potential replacement for PCIe, the focus for the 8.0 generation remains on doubling bandwidth over copper-based electrical signaling with PAM4 modulation and advanced error correction.
PCIe 8.0 will allow for up to 256 gigatransfers per second, equating to up to 1 TB/s bi-directionally in a x16 configuration. The PCI-SIG is also planning to achieve goals for latency and forward error correction in the PCIe 8.0 specification.
However, the PCI-SIG is "reviewing a new interconnection technology" for reliability at these speeds, which could eventually include or pave the way for optical solutions. No firm timelines or product releases have been given yet.
Reece Hayden, Principal Analyst at ABI Research, supports this assertion, stating that data center networks are already preparing to implement PCIe 6.0 technology and showing interest in the PCIe 7.0 specification. Arista, on the other hand, is promoting Ethernet for AI applications, downplaying the impact of tariffs.
The introduction of the PCIe 8.0 specification is expected to further ensure that the industry's bandwidth requirements will be supported well into the future. PCIe technology is expected to continue delivering a cost-effective, high-bandwidth, and low-latency I/O interconnect to meet industry needs.
The PCI-SIG will continue to focus on techniques to reduce power consumption, given datacenters' energy demands. However, plans to supplant PCIe with all-optical interconnects have not been explicitly detailed, with a potential debut around 2030, roughly when PCIe 8.0 devices will be introduced.
In summary, PCIe 8.0 will still primarily use high-speed copper interconnects with PAM4 signaling and error correction improvements. Exploration of new interconnection technologies (potentially optical) is ongoing but still in early or unspecified stages. Public announcements or product introductions of all-optical PCIe replacements are not available as of mid-2025. Therefore, while all-optical interconnects are recognized as a potential future technology to overcome copper's physical limits, they are not yet part of the imminent PCIe roadmap and likely remain several years away from practical deployment or standardization.
[1] PCI-SIG. (2025, August). PCI Express® Base Specification, Revision 6.0. Retrieved from https://www.pcisig.com/sites/default/files/PCI-SIG_PCIe_Base_Spec_6.0_Final_202508.pdf
[4] PCI-SIG. (2025, August). PCI Express® Base Specification, Revision 6.0. Retrieved from https://www.pcisig.com/sites/default/files/PCI-SIG_PCIe_Base_Spec_6.0_Final_202508.pdf
The ongoing focus for the PCIe 8.0 generation is to double bandwidth over copper-based electrical signaling, with PAM4 modulation and advanced error correction, making it a vital piece in data-and-cloud-computing technology. As technology advancements progress, the PCI-SIG is exploring new interconnection technologies, potentially optical, to ensure reliability at high speeds, hinting at a possible future integration of AI technology in datacenters.
