PCI Express 5.0 has only just started arriving on the consumer side, but the specification for PCIe 6.0 has just been finalized. The PCI Special Interest Group has published the final specs for PCIe 6.0, doubling the bandwidth over the 5.0 version up to a theoretical maximum bidirectional speed of 256GBps on an x16 slot (128GBps in a single direction).
The first super fast PCIe 5.0 SSDs appeared just before this year’s Consumer Electronics Show, promising read speeds of up to 14GBps. That was already twice what we’re used to seeing with PCIe 4.0 drives, and with the doubling PCIe 6.0 brings we’d expect to see SSDs offer up to 28GBps in the future.
Image: PCI Special Interest Group
PCIe 6.0 vs. existing PCIe specifications.
The PCI Special Interest Group has achieved the doubling of PCI Express speeds around every three years ever since the original introduction of the spec in 2003. PCIe 6.0 has overhauled the signaling technology to achieve the bandwidth gains this time, while maintaining low latency. It’s a move that Anandtech describes as “a more significant overhaul, arguably the largest in the history of the standard.”
The PCIe 6.0 architecture also maintains compatibility with all previous generations of PCIe. That will allow any existing hardware that uses earlier specifications to work in PCIe 6.0 hosts, and it will certainly help with adoption and the transition to this new specification.
While PCIe 5.0 is still in its infancy and being demonstrated with enterprise-grade SSDs, we shouldn’t expect to see PCIe 6.0 hardware for another 12 to 18 months. That means some servers will likely start to use the new spec at some point in 2023, with consumer hardware to follow in 2024 or 2025. Until then, get ready to hear a lot more about PCIe 5.0 SSDs, GPUs, and more throughout 2022.