PCIe 8.0 Announced With 256 GT/s For AI Workloads (nerds.xyz)
- Reference: 0178598670
- News link: https://hardware.slashdot.org/story/25/08/07/0222250/pcie-80-announced-with-256-gts-for-ai-workloads
- Source link: https://nerds.xyz/2025/08/pcie-8-0-specification/
> PCI-SIG [2]says PCI Express 8.0 will hit a raw bit rate of 256.0 GT/s, [3]doubling what PCIe 7.0 offers . The spec is expected to be ready by 2028, and the goal is to support massive data loads from AI, machine learning, edge computing, and even quantum systems. The group says PCIe 8.0 will allow up to 1 terabyte per second of bidirectional throughput with a full x16 configuration. They're also looking at new connector designs, improving protocol efficiency, reducing power use, and maintaining backward compatibility.
[1] https://slashdot.org/~BrianFagioli
[2] https://www.businesswire.com/news/home/20250805675479/en/PCI-SIG-Announces-PCI-Express-8.0-Specification-to-Reach-256.0-GTs
[3] https://nerds.xyz/2025/08/pcie-8-0-specification/
Only available with Windows 12! (Score:2, Insightful)
As is the Microsoft way
Perfectly Reasonable Power Draw (Score:3)
I mean, who doesn't have a smal RTG reactor in the back yard and an on-board fire extenguisher!
NVidia looks forward to melting even more mobos and PSUs in the future.
Re: Perfectly Reasonable Power Draw (Score:3)
RTGs have a very low power output.
bollocks (Score:2)
> the goal is to support massive data loads from AI, machine learning, edge computing, and even quantum systems
Nonsense. The goal is to have a faster bus. This is great no matter what you're doing with it because you can use fewer lanes to do the same job. All that shit is just buzzwording for attention. Look who it worked on.
Re: (Score:2)
Yeah, some marketing a-hole got involved. They can't go four words anymore without saying "AI". Total bull.
256 GT/s For AI Workloads (Score:3)
Cool to have 256 GT/s for AI workloads, but how fast is it for other workloads?
Re: (Score:2)
I know, right? There was no point in mentioning AI, it's just one of the million things computers are used for. I'll care about GPU throughput for gaming, not "AI".
Some marketing person must have involved themselves in the process, and inserting AI is their latest fad.
Where’s the new Bottleneck now? (Score:3)
With PCI reaching these speeds, I’m left wondering; what is the bottleneck now? Is “storage” on these systems a silly concept because it’s essentially ALL high-speed cache in memory, or forced to be because slowing down for it makes PCI advancements pointless? Just wondering where or what the future challenge will be in our endless pursuit of moar and faaaaster.
Also, that whole backward compatibility thing? Stop it. Just fucking stop it already. It smacks of the stupidity when talking EV “horsepower”. Time to grow up and move on. No one makes plans on a calendar a fortnight from now. Not sure why we’re worrying about supporting shit even half a decade old when it’s gonna take another decade just to get this to any market beyond the highly specialized ones justifying it. F1 race teams do not worry about being compatible with anything other than F1. You either justify your specialization, or you don’t.
Re: (Score:2)
On the backwards compatibility front, EV horsepower makes as much sense as a gasoline engine, sure we could say 'kilowatts' for both, but marketing loves the 'horse', especially since changing to kw would make the numbers go lower.
Problem on the compatibility front is that while you may safely ignore a 2005 PCIe adapter (or require such users to buy an adapter), breaking that compatibility form-factor wise also means breaking compatibility with 2025 adapters, which would be a much bigger problem. The most
Its the overhead of the "application stack" (Score:2)
> what is the bottleneck now?
The overhead of applications created by stacking thirty something libraries on top of each other to solve a problem a CS sophomore could directly code up.
GT/s ? (Score:2)
What is a GT/s? PCI-SIG technical workgroups will be developing the PCIe 8.0 specification with the following feature objectives (so, a press release)
Re: (Score:2)
> What is a GT/s? PCI-SIG technical workgroups will be developing the PCIe 8.0 specification with the following feature objectives (so, a press release)
Still stands for Gran Turismo I’d imagine, since our minds are practically racing around the ol’ clickbait track.
Re: (Score:2)
GT/s. transfers per second and its more common secondary terms gigatransfers per second
It's basically marketing wank that was originally designed to sell DDR ram as, ex, "2400MT" when running on a 1200mhz bus.
Giga-Teslas per second ?? (Score:2)
Honstly... [1]https://en.wikipedia.org/wiki/... [wikipedia.org]
Why are we now using GT/s to mean "giga-transfers per second"? FFS
It's bad enough the people in the US use "milli-Teslas" to mean "metric tonnes".
[1] https://en.wikipedia.org/wiki/Tesla_(unit)
Re: (Score:2)
What is it in pico-hiters?
Whoah, slow down cowboy!! (Score:2)
My gaming PC motherboard is on version 4, and I didn't buy that all that long ago.
Image the cool case LED animations ... (Score:2)
> My gaming PC motherboard is on version 4, and I didn't buy that all that long ago.
Sure, but with PCIe 8 imagine the cool LED animations you could have in and on your PC case without taking a noticeable hit during gameplay. I mean we could probably replace all of those LEDs with tons of tiny OLED displays. :-)
Timeline (Score:4, Informative)
With a specification coming out in 2028, that means the very first (enterprise, high-end) products can be expected 2030 at the earliest. And that's based on past (PCIe5 and earlier) rapid adoption. PCIe6 was standardized three years ago and there are still no motherboards.
Re: Timeline (Score:2)
Informative. Anyone have perspectives on causes of product release slowness for any PCI standard generation? Insufficient current demand? High development or production costs? Technical challenges?
Re: (Score:3)
Other than servers and high end workstations, there's also absolutely no need for even pcie5 yet. The most powerful gpus barely need pcie4 still, and ssds are about 100M/s for 4k transfer speeds, the most important metric for 99% of users other than marketing wank.
Add to this the fact that faster speeds make hotter components. And more importantly the fact that routing even pcie5 traces is already veering on the edge of black magic... The money quote from tomshardware on pcie8 [1]https://www.tomshardware.com/t [tomshardware.com]
[1] https://www.tomshardware.com/tech-industry/pci-sig-announces-pcie-8-0-spec-with-twice-the-bandwidth-1tb-s-of-peak-bandwidth-256-gt-s-per-lane-and-a-possible-new-connector
Re:Timeline (Score:5, Informative)
> . The most powerful gpus
Let me stop you there. GPU's haven't defined the limits for PCI bandwidth for a while now. Parallel storage arrays for NVMe drives, and chip to chip interconnectors are the big use case for the bandwidth. Your PC is currently very much constrained in bandwidth as the motherboard has limited amount of lanes for certain tasks which get split into multiple duties. Take for example your GPU. Got a 16x GPU on the motherboard? It won't get 16x lanes if you share the slot next to it with a NVME riser since the 16x slots are almost universally multiplexed unless you a buying a high end threadripper board. Got 3 NVME drives? Congrats, the performance of one of them will absolutely crater when a high bandwidth USB device is plugged into the "wrong" port as even high end X870 boards can only connect 2 NVME slots to the processor itself while the rest go through a chipset and share their lanes with a myriad of other devices. And that's before you consider that there are actually PCIe 6.0 SSDs on the market [1]https://www.micron.com/product... [micron.com]
But beyond that these products aren't designed for you. They are designed for the types of people who would put say multiple NVIDIA ConnectX Infiniband adapters together into a switch, or connect their PCIe 6.0 interface to 4 hosts concurrently providing each with 16x lanes.
The high performance computing industry laughs at your little toy GPU use case.
> The money quote from tomshardware on pcie8
You misunderstood the money quote. The quote is about a massively parallel board edge interconnector, not the traces on the PCB. We absolutely are capable of doing fast signaling on the PCB itself and in single signals through to antennas and through some connectors, the issue here is connecting two PCBs together in a cheap way (currently one side of the interconnector is just a raw PCB without an actual connector at all, and this keeps costs low).
[1] https://www.micron.com/products/storage/ssd/data-center-ssd/9650-ssd
Re: (Score:3)
Yeah all that is nice and dandy, and I agree with it, but this is exactly why I started my post with "other than servers and high end workstations". Because op was talking about motherboards, which is not exactly where you start talking about inifiniband. Notice also e.g. for your first paragraph that I explicitly mentioned dedicated lanes in my post, too.
Wrt the quote, I suppose I could have worded that paragraph better, but I thought that a quote talking about interconnects would be taken as talking about
Re: (Score:2)
Is it all just aspirational? Or more nicely put, a goal they don't yet know how to achieve? If that's the case, why stop at 8? Why not announce the speeds of gens 9-28 now and fill in the details as they go?
Re: Timeline (Score:2)
Internal development with the draft specification is already on everyone's roadmap. Product release of many vendors will be the same year as the final spec.