A key standard to double data transfer speeds between major computer components will be finalized in a few months.
The final specification of PCI-Express 6.0 is slated for late this year or early 2022, said Al Yanes, president and chairman of the standards organization PCI-Special Interest Group. The register this week.
“Typically, we typically see products using the latest PCIe architecture 12-18 months after the release of the final specs,” Yanes added.
You know the drill: PCIe typically connects microprocessors, GPUs, IO devices, and data storage in systems ranging from home PCs and cloud servers to some integrated devices. PCI-SIG is in the final stages of spec approval and has released what may be its last revision, version 0.9, today.
The new specification will succeed PCI-Express 5.0, which was finalized in 2019.
Specification 6.0 supports up to 64 gigatransfers per second, which in practice means up to 128 GB / s per direction in an x16 configuration, which is double that of PCIe 5.0. By comparison, PCI-Express 1.0, released in 2003, had a transfer rate of 2.5 GT / s, which translates to 4 GB / s per direction with x16. PCI-Express 6.0 will be backwards compatible with previous generations, we are told. Upgrades to PCI-Express standards have been done in two-year increments since PCIe 4.0, which was ratified in 2017.
Faster transfer rates are needed due to the increase in data-intensive applications that include artificial intelligence, Yanes said.
“The bandwidth capabilities of PCIe 6.0 technology are more suited to high-end applications today …
The protocol has acquired a low latency data error correction mechanism called forward error correction (FEC), in addition to CRC, to make increasing bandwidth viable. It is also worth noting that it uses PAM-4 [PDF] encoding, which is seen in Fast Ethernet and GDDR6X. There are other tricks up its sleeve – a technical preview is here [PDF].
It will be some time before PCs get PCIe 6.0 interfaces. If it’s not because extra care will have to be taken to have motherboards capable of handling high-speed signaling, then the chipsets simply won’t be ready.
An Intel spokesperson declined to comment when it would add PCIe 6.0 support to its components, although it did say it supports PCIe 5.0 in future processors named Alder Lake; its Sapphire Rapids and Ponte Vecchio will also support PCIe 5.0. Otherwise, the latest 11th Gen Intel Xeon and Core parts support PCIe 4.0.
A spokesperson for Nvidia declined to comment when it would bring support for PCIe 6.0. The company’s chips, like the BlueField-3 DPU for data centers, can handle PCIe 5.0. AMD did not respond to a request for comment. Note that the most recent desktop and data center chips in the industry support PCIe 4.0.
The evolving automotive industry is at the forefront of semiconductors and PCI-SIG is looking to capitalize on it.
“We have seen enormous interest in automotive solutions and have formed a new PCIe technical working group to focus on how to increase the adoption of PCIe technology in the automotive industry due to the increased demand for bandwidth in this ecosystem, ”Yanes said. ®