No PCIe Gen5 for "Raphael," Says Gigabyte's Leaked Socket AM5 Documentation

[btarunr]

AMD might fall behind Intel on PCI-Express Gen 5 support, say sources familiar with the recent GIGABYTE ransomware attack and ensuing leak of confidential documents. If you recall, AMD had extensively marketed the fact that it was first-to-market with PCI-Express Gen 4, over a year ahead of Intel's "Rocket Lake" processor. The platform block-diagram for Socket AM5 states that the AM5 SoC puts out a total of 28 PCI-Express Gen 4 lanes. 16 of these are allocated toward PCI-Express discrete graphics, 4 toward a CPU-attached M.2 NVMe slot, another 4 lanes toward a discrete USB4 controller, and the remaining 4 lanes as chipset-bus.

Socket AM5 SoCs appear to have an additional 4 lanes to spare than the outgoing "Matisse" and "Vermeer" SoCs, which on higher-end platforms are used up by the USB4 controller, but can be left unused for the purpose, and instead wired to an additional M.2 NVMe slot on lower-end motherboards. Thankfully, memory is one area where AMD will maintain parity with Intel, as Socket AM5 is being designed for dual-channel DDR5. The other SoC-integrated I/O, as well as I/O from the chipset, appear to be identical to "Vermeer," with minor exceptions such as support for 20 Gbps USB 3.2x2. The Socket has preparation for display I/O for APUs from the generation. Intel's upcoming "Alder Lake-S" processor implements PCI-Express Gen 5, but only for the 16-lane PEG port. The CPU-attached NVMe slot, as well as downstream PCIe connectivity, are limited to PCIe Gen 4.



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[TheLostSwede]

Not sure why this should come as a surprise to anyone.
However, I am surprised they didn't widened the interface to the chipset, but I guess the workaround was to add four more PCIe 4.0 lanes to the CPU for USB4/Thunderbolt support.
This also makes it clear that AMD is going for DP 2.0.

 

[AnarchoPrimitiv]

Epyc Genoa will have PCIe 5.0, and that's actually where it's needed, but PCIe 5.0 seems to me to be a completely unnecessary marketing point for a consumer platform at this time (or even in a years time) that only has the potential to drive up costs. The overwhelming majority of people still don't even have a second gen PCIe 4.0 NVMe SSD, and we can all agree that the difference between a PCIe 3.0 NVMe SSD and a 4.0 SSD is imperceptible. This article implies that when AMD made the switch to PCIe 4.0, it is comparable to this situation, when that's hardly the case considering PCIe 3.0 was released in 2010 and the first PCIe 4.0 motherboards were released in 2019....that's nine years, whereas PCIe 4.0 has only been around for approximately two years and hasn't even been fully saturated yet by a GPU.

 

[john_]

With AMD going first to PCIe 4.0, we didn't see manufacturers really using that standard. With Intel going to PCIe 5.0 we might see manufacturers, even huge ones like Samsung, coming out with good solutions for it.
But I doubt PCIe 5.0 will bring anything interesting in the first year or two. We are fully covered on SSDs and probably going PCIe 5.0 will have minimal impact on graphics card performance. As always.
Also considering that PCIe 4.0 was used on SSDs, not to push higher speeds at lower prices, but instead push prices higher, who really needs an 1TB SSD that can score 14GB/sec sequencial speed, if it costs $300-$400?

 

[W1zzard]

But I doubt PCIe 5.0 will bring anything interesting in the first year or two.

I think the biggest improvement is that you can now make do with fewer lanes and not lose performance. i.e. x2 for SSD and x8, or even x4 for graphics, which gives you much better expansion options. For this we need good bifurcation support, so lanes can be rerouted dynamically, which might be complicated with the signal integrity requirements.

 

[LTUGamer]

I am planing to build a bomb!

I need leaked data from gigabyte PSU department. They have developed some great bombs.

 

[JAB Creations]

M.2/NVMe drives don't boot faster than SATA and very few people equipped with a PCI-Express 5.0 system will notice any benefits of 5.0 over 4.0. Yes, there are a few though the article is written like AMD somehow has an inferior platform because something the vast majority of even enthusiasts wouldn't notice.

 

[john_]

I think the biggest improvement is that you can now make do with fewer lanes and not lose performance. i.e. x2 for SSD and x8, or even x4 for graphics, which gives you much better expansion options. For this we need good bifurcation support, so lanes can be rerouted dynamically, which might be complicated with the signal integrity requirements.

When PCIe 4.0 came out, I was thinking the same. When AMD's 570 came out, I was thinking the same. But companies want profits. What I was thinking and what you are thinking, is something that would have happened 15 years ago, but not today.
We didn't saw cheaper PCIe 4.0 SSDs running on PCIe 4.0 x2 or even PCIe 4.0 x1. We saw just more expensive PCIe 4.0 x4 SSDs.
We show motherboards with AMD 570 to have 3 PCIe x16 slots and two of them connected to the chipset, instead of the two first be connected to the CPU and have the option to split PCIe lanes from X16 to x8 + x8. I was talking back then about "micro ATX boards, build to look like full ATX boards" and many where totally against this opinion.

Anyway, I doubt what you say and it should be basic logic to prevail over higher profit margins.

 

[W1zzard]

When PCIe 4.0 came out, I was thinking the same. When AMD's 570 came out, I was thinking the same. But companies want profits. What I was thinking and what you are thinking, is something that would happen 15 years ago, but not today.
We didn't saw cheaper PCIe 4.0 SSDs running on PCIe 4.0 x2 or even PCIe 4.0 x1. We saw just more expensive PCIe 4.0 x4 SSDs.
We show motherboards with AMD 570 to have 3 PCIe x16 slots and two of them connected to the chipset, instead of the two first be connected to the CPU and have the option to split PCIe lanes from X16 to x8 + x8. I was talking back then about "micro ATX boards, build to look like full ATX boards" and many where totally against this opinion.

Anyway, I doubt what you say and it should be basic logic to prevail over higher profit margins.

I'm afraid you are 100% correct, great input

 

[TheLostSwede]

With AMD going first to PCIe 4.0, we didn't see manufacturers really using that standard. With Intel going to PCIe 5.0 we might see manufacturers, even huge ones like Samsung, coming out with good solutions for it.
But I doubt PCIe 5.0 will bring anything interesting in the first year or two. We are fully covered on SSDs and probably going PCIe 5.0 will have minimal impact on graphics card performance. As always.
Also considering that PCIe 4.0 was used on SSDs, not to push higher speeds at lower prices, but instead push prices higher, who really needs an 1TB SSD that can score 14GB/sec sequencial speed, if it costs $300-$400?

Eh? So the fact that we have a bunch of PCIe 4.0 NVMe SSDs and a both AMD and Nvidia supporting PCIe 4.0 for their current graphics cards and new PCIe 4.0 multi-gigabit Ethernet controllers turning up, equals no support to you?
You're aware it takes some time to make these things, right? It's not just an interface you can easily swap out when you feel like it.
And as to your other comment, we are actually starting to see devices that are using fewer lanes. Look at Marvell's new AQC113 10Gbps Ethernet controller, it can use a single PCIe 4.0 lane for 10Gbps speeds, instead of four PCIe 3.0 lanes. On top of that, it's in a BGA packaging instead of FCBGA, which makes it cheaper to produce. So in other words, we are seeing cheaper devices that use fewer lanes, but it doesn't happen over night.

 

[TumbleGeorge]

Lol dudes if engineers was read this commens and got attention, we must be happy if have today MB's with ordinary PCI 2.3, or max AGP 4X. Who needs of something more?

 

[Jism]

PCI-E 5.0 is only usefull in enterprise based hardware, not consumers. It will take a while before PCI-E 4.0 could fully be taxed. Otherwise it's just a gimmick with no real world benefit.

 

[MaMoo]

I am planing to build a bomb!

I need leaked data from gigabyte PSU department. They have developed some great bombs.

Gigabye PSU. That's also the best lesson in PC building - never skimp on the quality of the PSU. Go with a good brand and platform/OEM.

 

[GreiverBlade]

i have yet to use a Gen4 hardware... and that would be a XPG S70 1tb that would replace my 512gb S11 Pro and offer a bit more than double the speed ... nonetheless ... that would not give me any real life advantage outside benchmark ... well ... loading time would be shorter, but what's shorter than a few seconds (no need to answer i know it, but is it needed?) still the difference in price between a S11 and a S70 is a "mere" 30chf ... why not, in the end.
graphic card of the actual Gen use Gen4 i know ... but ...

so, AMD will not offer that and maybe focus on something else? fine by me...

 

[Aretak]

Motherboard prices went way up when Gen 4 was implemented. Scary to think how much Z690 is going to cost with a bleeding edge Gen 5 implementation. And all for something which is of no use for 99.99% of people who'll buy these desktop CPUs. Sticking with Gen 4 seems like the right move in the medium term.

 

[john_]

Eh? So the fact that we have a bunch of PCIe 4.0 NVMe SSDs and a both AMD and Nvidia supporting PCIe 4.0 for their current graphics cards and new PCIe 4.0 multi-gigabit Ethernet controllers turning up, equals no support to you?
You're aware it takes some time to make these things, right? It's not just an interface you can easily swap out when you feel like it.
And as to your other comment, we are actually starting to see devices that are using fewer lanes. Look at Marvell's new AQC113 10Gbps Ethernet controller, it can use a single PCIe 4.0 lane for 10Gbps speeds, instead of four PCIe 3.0 lanes. On top of that, it's in a BGA packaging instead of FCBGA, which makes it cheaper to produce. So in other words, we are seeing cheaper devices that use fewer lanes, but it doesn't happen over night.

I can include smiles too

My English are far from perfect, but I am pretty sure that "we didn't see manufacturers really using that standard" is somewhat different from "equals no support to you".
SSD manufacturers came up with PCIe 4.0 models that where not much better than PCIe 3.0 models, with the exception of sequential speeds. If I am not mistaken, Samsung didn't really rushed to come out with PCIe 4.0 solutions either. And as for PCIe 4.0 with graphics cards, it's just normal for the manufacturers to use the latest version of the bus, but my point was that 4.0 doesn't offer much compared to 3.0 version in 3D performance, something that is usually the case in all those last years. Not just this last generation.

Now my point exactly is that. Now that Intel will come out with PCIe 5.0 support, we will see how difficult it is to create PCIe 5.0 SSDs that are clearly faster than previous generations SSDs in about every benchmark. I wouldn't remember your post by then, I hope you would and you would mention me either to tell me that I was wrong, or either to tell me that probably I was right.
About that AQC113. Was it available after AM4 came out or after Intel supported PCIe 4.0? If it was way before Intel supported 4.0, then we have an example. But still I believe it is an exception, not the rule.

Finally, more smiles!!!!!

 

[Valantar]

Eh? So the fact that we have a bunch of PCIe 4.0 NVMe SSDs and a both AMD and Nvidia supporting PCIe 4.0 for their current graphics cards and new PCIe 4.0 multi-gigabit Ethernet controllers turning up, equals no support to you?
You're aware it takes some time to make these things, right? It's not just an interface you can easily swap out when you feel like it.
And as to your other comment, we are actually starting to see devices that are using fewer lanes. Look at Marvell's new AQC113 10Gbps Ethernet controller, it can use a single PCIe 4.0 lane for 10Gbps speeds, instead of four PCIe 3.0 lanes. On top of that, it's in a BGA packaging instead of FCBGA, which makes it cheaper to produce. So in other words, we are seeing cheaper devices that use fewer lanes, but it doesn't happen over night.

I think integrated components like Ethernet controllers is one of the more realistic places to see this come true, as they don't have to care as much about backwards compatibility. With SSDs on the other hand, I would love to see 4.0 x2 NVMe become a thing for fast, cheap(er) drives, but given that those would be limited to 3.0 x2 on older boards/chipsets and thus lose significant performance (at least in bechmarks) and would be pissed on by literally every reviewer out there for this ("yes, it's a good drive, but it sacrifices performance on older computers for no good reason" alongside the inevitable value comparison with a just-launched MSRP product vs. one that has 6-12 months of gradual price drops behind it), I don't see it happening, even if they would be great drives and would allow for more storage slots per motherboard at the same or potentially lower board costs.

That's the problem with adopting new standards in open ecosystems with large install bases - if you break compatibility, you shrink your potential customer base dramatically.

Overall, I think this is a very good choice on AMD's part. The potential benefits of this are so far in the future that it wouldn't make sense, and the price increase for motherboards (and development costs for CPUs and chipsets) would inevitably be passed on to customers. No thanks. PCIe 4.0 is plenty fast. I'd like more options to bifurcate instead, but 5.0 can wait for quite a few years.

 

[Vya Domus]

PCI-E 5.0 is only usefull in enterprise based hardware, not consumers.

Theoretically a faster interface between CPU, GPU and storage could open up the possibility of many performance improvements. It's a feedback loop, faster interfaces are not useful because software is written with the slower interfaces in mind but software is written that way because there are no faster interfaces.

People only think about this in the context of current graphics APIs and how they interact with GPUs. Well, of course there is mostly nothing to be gained by increasing the speed of PCI-e because those APIs are stuck on top of the model of "PCI-e is slow".

 

[Valantar]

Theoretically a faster interface between CPU, GPU and storage could open up the possibility of many performance improvements. It's a feedback loop, faster interfaces are not useful because software is written with the slower interfaces in mind but software is written that way because there are no faster interfaces.

People only think about this in the context of current graphics APIs and how they interact with GPUs. Well, of course there is mostly nothing to be gained by increasing the speed of PCI-e because those APIs are stuck on top of the model of "PCI-e is slow".

But software isn't even close to utilizing the interfaces we have today, and arguably the ones we've had for a decade in slots/half a decade in SSDs. So, if the adjustment cycle for developers to start adjusting to these new system affordances is >5 years, what is the benefit of pushing for adoption of a new standard now, when we're at best two years into the availability cycle of the current one?

In more plain language: given that software isn't making real use of PCIe 3.0, and we have 4.0 already widely available, what benefit does 5.0 bring, even in the future?

 

[ZoneDymo]

Motherboard prices went way up when Gen 4 was implemented. Scary to think how much Z690 is going to cost with a bleeding edge Gen 5 implementation. And all for something which is of no use for 99.99% of people who'll buy these desktop CPUs. Sticking with Gen 4 seems like the right move in the medium term.

also add to that the supposed 12VO standard.....700 dollar motherboards?

 

[Valantar]

also add to that the supposed 12VO standard.....700 dollar motherboards?

What realistic price increase does 12VO bring with it? A couple of 12V buck converters for 5V and 3.3V really aren't going to change the BOM much.

 

[windwhirl]

What realistic price increase does 12VO bring with it? A couple of 12V buck converters for 5V and 3.3V really aren't going to change the BOM much.

You'd need a different PSU, wouldn't you? Regardless, the motherboard manufacturers were pushing back against that standard, last I heard.
Motherboard manufacturers unite against Intel's efficient PSU plans | PC Gamer
Though, take it with a grain of salt, as always.

The overwhelming majority of people still don't even have a second gen PCIe 4.0 NVMe SSD

I'd argue the overwhelming majority of people don't even have any kind of PCIE 4.0 SSD at all, either from that first wave which were basically 3.0-era with 4.0 controller or the newer ones.

 

[Vya Domus]

But software isn't even close to utilizing the interfaces we have today, and arguably the ones we've had for a decade in slots/half a decade in SSDs.

That's the point, the software is designed to utilize the interfaces as little as possible because they're slow.

 

[Valantar]

That's the point, the software is designed to utilize the interfaces as little as possible because they're slow.

Uh ... are PCIe 3.0 and 4.0 slow? If so, why are we nowhere near making proper use of them? What you're saying would have made sense if we were still stuck on SATA. With PCIe 3.0 NVMe drives being common for half a decade, this is nowhere near accurate. If development is still stuck in the early 2010s, that's on developers, not the availability of fast interfaces.
(Yes, obviously the need for flash parallelism and the cost inherent to this is also an issue restricting performance, but most decent 3.0 drives can maintain random 4k speeds far above what most applications will ever come close to making use of.)

You'd need a different PSU, wouldn't you? Regardless, the motherboard manufacturers were pushing back against that standard, last I heard.
Motherboard manufacturers unite against Intel's efficient PSU plans | PC Gamer
Though, take it with a grain of salt, as always.

Sure, but what does that have to do with motherboard prices? Last I checked, the PSU is separate

And I would expect motherboard makers to push back - they're a notoriously conservative lot (plus are corporations producing largely commodity products with low margins under late-stage capitalism), and have no interest in taking on the expenditure of adapting to new standards just because they would benefit consumers, the environment, etc. My hope: that OEMs already using 12VO-like proprietary solutions shift over to 12VO, leading to opportunities for slow and steady growth in replacement PSUs, opening the door for niche motherboards as well. 12VO would be great for ITX boards, saving potentially a lot of board space with only the 10-pin connector needed (and the necessary buck converters being small and quite flexible in where they are placed). But I don't have any real hope for this becoming widely available in the next 5+ years, sadly.

 

[Punkenjoy]

I think AMD should be supporting this as soon as possible but since they use a chiplets design, I am not too worry that they will update the I/O die as soon as they think it will be worth it. That will also allow them to release a new series of processors with a new set of motherboards. (yep ! but hey AMD is a for profits organization).

As for the utility of PCI-E Gen 5, well, the more the better all the time. But on the GFX side, Devs try to make sure PCI-E is a non-issue. It was quite easy because most of the market were on Gen3 16X. Theses day with the lower cards like the 6600XT that are only 8X, that change a bit. But before things like Direct Storage and sampler feedback. (As long as the storage can follow).

With Sampler Feedback, you could load twice the amount of texture mipmap during a standard frame duration. (Or load the same amount of data faster to get higher fps since you don't have to wait for the data).

The more bandwidth the better. Build it and they will come. If on Intel, PCIE Gen 5 cost just a little bit more, it should be one of the selling point. Not the main one indeed, but still one of it.