Fouth Gen PCIe Sees Bandwidth Double

PCI has been the de facto standard for PC expansion slots and now we have the first details about the fourth generation of the PCI express spec. PCIe 4.0 will have a base speed of 16 Gbps per data link. Graphics cards, which are typically among the most data-hungry components in a machine, can use up to 16 of these links for a total throughput of 64 GB/s vs. today's maximum of 32.

Right now, there are several companies all vying for the chance to draft the new standard. Hardware manufacturers try to agree on one specific plan for these updates to help streamline the experience for end users. And with more devices needing greater speeds to take full advantage of their potential, this is a welcome update.

It's also expected to cut costs, as odd as that sounds. In the same way that shifting to a smaller manufacturing process for CPUs and GPUs can help cut costs by reducing component waste and helping systems run more efficiently, moving to a quicker expansion slot speed means manufacturers can use fewer data links or assign more tasks to each one, cutting down the total cost dramatically.

PCIe 4.0 could be even more valuable in the mobile space, where size, cost and efficiency are even greater concerns. With M-PCIe, manufacturers are beginning to adapt to the shifting landscape of computing. Mobile devices can take advantage of a second interlink called M-Phy, which can help enhance the performance of video cameras and communications chips in tablets and smartphones.

No matter how you slice it, PCIe's fourth generation is an exciting and welcome boost to current tech. Here's hoping we'll see that standard surface sooner, rather than later.

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  • djtronika
    Fouth. I can't read any further.
  • Other Comments
  • djtronika
    Fouth. I can't read any further.
  • velocityg4
    Does anything out there even come close to saturating PCI-e 3.0 x16? All I can think of would be the enterprise segment with massive RAID arrays, SSD RAID, fiber optic networking and cluster computing.

    It would be nice if PCI-e would become mainstream for SSD not just relatively expensive cards for enthusiasts. As SATA III seems to be a hindrance as the SATA spec isn't keeping pace. While Apple is the only one I see taking advantage of PCI-e for SSD in mainstream computers getting about 1 GBPS. Heck they're the only ones that seem to be interested in switching their lines to any type of SSD.
  • InvalidError
    64GB/s is more than twice the amount of system memory bandwidth in most PCs today. At this point, it would almost start to make sense to start using GPU memory as system memory for things that depend heavily on bandwidth instead of low latency.

    Note: to get 64GB/s out of PCIe4, you need to simultaneously receive and transmit 32GB/s each way.