Sometimes the technology industry moves too fast. We’ve just started rolling out PCIe 4.0 to consumer products, PCIe 5.0 is just rolling out, and PCIe 6.0 is on its way. What kind of animal?
In early January 2022, the PCI Special Interest Group (PCI-SIG) published the final specifications for PCIe 6.0, the latest version of the popular interface standard that connects things like graphics cards, SSDs, and network cards to your PC.
As we’ve seen in previous transitions, PCIe 6.0 promises faster transfer rates and backwards compatibility with your favorite old sound card. We wouldn’t have such fast computers without PCIe, but an excess of standards could make the next few years a little messy.
What is PCI?
PCIe stands for Peripheral Component Interconnect Express (PCIe) standard. This is the main way to connect expansion cards such as sound cards, graphics cards, and network cards to your PC. It is also used for these tiny and fast NVMe M.2 SSDs, but M.2 drives use a dedicated slot that expansion cards don’t have.
If you’ve ever built a PC or looked at a motherboard in recent years, then you’ve seen a PCIe slot. Edge connectors come in four main varieties: x16, x8, x4, and x1. Most of the time, you can tell them apart, since the x16 slots are the big ones, while the rest get progressively smaller. However, this is not always the case, as sometimes an x16 slot actually only supports x8.
The “x” numbers indicate the number of data lines connected to this slot on the motherboard. The greater the number of transmission lines, the greater the potential throughput for that slot. Typically, you need a graphics card connected to an x16 slot, while other cards can usually use whatever is available, depending on your motherboard’s PCIe slot configuration.
PCIe also has the advantage of being backward compatible with all previous versions of the standard. For example, a card designed for PCIe 2.0 will still work in a PCIe 6.0 slot, provided you can get the correct software drivers to work with the device.
What’s new in PCIe 6.0?
The PCIe standards are set by the PCI Special Interest Group, which sets the specifications for PCIe. The goal of PCI-SIG was to roll out a new PCIe standard every two or three years, effectively doubling the bandwidth of previous versions. As expected, PCIe 6.0 does just that.
PCIe 6.0 x16 slots have a maximum bidirectional throughput of 256 gigabytes per second (GB/s), compared to 128 GB/s for PCIe 5.0. To understand what this means, imagine that you have a graphics card in a PCIe 6.0 slot. This bidirectional bandwidth value indicates the total amount of data that the card can send to the CPU and that the CPU can send back to the card. In the case of PCIe 6.0, that means 128 GB/s each way, for a total of 256 GB/s.
Now let’s compare this to PCIe 3.0, which has been the standard for years and is still widely used in the home today, unless you built or bought a new PC from 2019 or 2020 (and paid a premium for it).
The maximum PCIe 3.0 speed is 32 GB/s in x16 slot. Thus, PCIe 6.0 has eight times the bandwidth of its predecessor, which is still widely used. It’s an insane upgrade, but modern games can’t even come close to saturating that kind of bandwidth. The most notable improvement we’re likely to see in the early days has to do with NVMe SSD speeds, as we saw with the move to PCIe 4.0 – SSDs typically use 4 PCIe lanes. But when exactly can you experience this faster standard at home?
When will we see PCIe 6.0?
PCI-SIG estimates that PCIe 6.0 hardware will not hit the market until 12 to 18 months after the publication of the new standard. PCIe 6.0 was announced on January 11, 2022, so we expect PCIe 6.0 products to be released in late 2022 or early 2023.
This is at best. We are likely looking at early examples of PCIe 6.0 in mid to late 2023, which in all likelihood will not be aimed at consumers.
All the bandwidth promised by PCIe 6.0 is really needed in areas that rely on machine learning and artificial intelligence. This includes the automotive and aerospace industries, data centers, and so on. This is where PCI-SIG looks forward to seeing PCIe 6.0 first after hardware manufacturers figure out how to turn the spec into actual products.
For the consumer market, this may take some time as processor manufacturers (AMD and Intel) and their manufacturing partners have to figure out when to release hardware that supports PCIe 6.0. We’ve barely entered the era of PCIe 4.0 for home PCs right now. AMD released the first PCIe 4.0-enabled processors to consumers in mid-2019, while Intel didn’t do so until early 2021. In terms of graphics cards, AMD released its first PCIe 4.0 GPUs around the same time as CPUs, with NVIDIA following suit in 2020.
So what happens next? Who knows? When the move to PCIe 4.0 began, graphics cards—the most resource-hungry PCIe devices on consumer PCs—didn’t even use the maximum bandwidth of PCIe 3.0. How soon gamers or video editors will need PCIe 6.0 is unclear. However, as AnandTech points out, the move to PCIe 6.0 could mean lower prices. Since PCIe 6.0 graphics cards are unlikely to require larger x16 connections, this could result in lower hardware costs for PC buyers while maintaining the maximum bandwidth of current graphics cards.
Given the benefits, we hope the transition to PCIe 6.0 will happen fairly quickly, as long as technical hurdles don’t cause major delays. Since PCIe 4.0 and 5.0 are already pushing against each other, it makes sense to skip this mess and upgrade to PCIe 6.0 as soon as possible.
No one can guess if Intel, AMD and computer manufacturers planned this. But don’t let the upcoming migration to PCIe 6.0 stop you from getting a new PC or laptop . If you need a new computer, it’s best not to worry about waiting for a potential latest and greatest on an unspecified date.