Computers have taken advantage of the ultra-fast communication speed that fiber optics can provide for a long time. However, this is the first time it could potentially become a standard internal component of our PCs, with semiconductor fiber optics specialist Cadence demonstrating a new fiber optic PCIe 7.0 interface.
The world’s first demonstration is still a proof of concept rather than a definite finished product, but it shows the potential of the technology. The interface can clock in at 128GT/s (242GB/s for an x16 connection), which is four times faster than the current 32GT/s (63GB/s for x16) rate of PCIe 5.0. It’s too early to know if it will be a technology that finds its way into the best gaming motherboards of the near future, but it’s an interesting concept nonetheless.
Instead, the more likely application for this tech demo would be in PCIe interconnects between servers where, particularly with modern AI workloads, it’s seen as advantageous to have multiple PCs communicating with ultra-fast connections. Indeed, at its Computex 2024 keynote, Nvidia was highly enthusiastic about its new server backbone (below), which reminded us of a huge version of the SLI clips you used to get when connecting two graphics cards together.
However, this fiber optic technology could be used in PCs to create longer graphics card PCIe extension cables. We can envisage a slim, round cable protruding from a laptop or compact desktop PC, and then connecting to an external graphics card box that’s situated under your desk or otherwise out of the way.
Version 0.5 of the PCIe 7.0 spec was released earlier in 2024, and it’s expected to incorporate a standard copper-based PCB standard that’s able to deliver the same 128GT/s bandwidth as the optical version. It’s also expected to be finalized in 2025, with boards and other technologies based on the standard arriving some years later.
For comparison, the final PCIe 6.0 specification was signed off in January 2022, but it was only in March this year that Nvidia announced that its Blackwell AI accelerators and new NVLink 5 standard would use the PCIe 6.0 interface.
While we wait for our fiber optic PC future, check out this fiber optic gaming PC that uses the technology in a very different way to create a stunning-looking starfield visual effect.