PCIe 4.0 wont be supported on B450, X470 and older chipsets

[leadeater]

2 minutes ago, Drak3 said:

That's the first thing I've seen that says it doesn't use it.

Thought it was more common knowledge than it is maybe, most reviews I watched mentioned this fact. Below is from the actual Anandtech review where they reconfirm it is limited to 3.0.

 

https://www.anandtech.com/show/13923/the-amd-radeon-vii-review/3

[Drak3]

3 minutes ago, leadeater said:

Thought it was more common knowledge than it is maybe, most reviews I watched mentioned this fact. Below is from the actual Anandtech review where they reconfirm it is limited to 3.0.

Seeing as AMD doesn't list a PCIe spec, Anandtech doesn't list a source to the confirmation, and there is no way to check if it is PCIe 4.0 without a 4.0 system, I'm not going to conclude that it is limited to 3.0 until AFTER Ryzen 3000 and a few driver updates.

[RejZoR]

I'm guessing it only applies to PCIe lanes that come with CPU itself (which is why Zen2 is required). All the extra ones from chipset would still be PCIe 3.0. Makes sense since we always get some PCIe lanes from CPU and some from chipset. And sloting in a newer CPU with newer PCIe, it would update lanes as well. If there was physical change, not, but here it seems to be electrical only.

[leadeater]

9 minutes ago, Drak3 said:

Seeing as AMD doesn't list a PCIe spec, Anandtech doesn't list a source to the confirmation, and there is no way to check if it is PCIe 4.0 without a 4.0 system, I'm not going to conclude that it is limited to 3.0 until AFTER Ryzen 3000 and a few driver updates.

That information came from AMD. Yes AMD's product page doesn't mention it, it doesn't mention PCIe specs at all. Radeon VII does not have PCIe 4.0, that information was given out in the reviewers information packs. If it were incorrect AMD would have required this information to be corrected.

 

Quote

PCI Express 4.0 transfer rates, supported on Radeon Instinct MI50 and MI60, are still disabled though, as are the Instinct cards’ Infinity Fabric links. According to AMD, Radeon VII’s compute capabilities size up to Radeon RX Vega 64 and Radeon Instinct MI60 as follows:

https://www.tomshardware.com/reviews/amd-radeon-vii-vega-20-7nm,5977.html

 

They aren't just making it up.

 

Edit:

Quote

Sadly, the Radeon VII will only ever feature a PCIe 3.0 connector despite the fact that Ryzen 3rd Generation processors will support PCIe 4.0 technology, which will double the throughput of connected devices. 

https://www.techradar.com/au/reviews/amd-radeon-vii

 

Quote

AMD has also disabled PCIe 4.0, limiting the Radeon VII to the more commonly used PCIe 3.0 interface, which is not an issue either.

https://www.techspot.com/review/1789-amd-radeon-vii/

[porina]

Quote

Sadly, the Radeon VII will only ever feature a PCIe 3.0 connector despite the fact that Ryzen 3rd Generation processors will support PCIe 4.0 technology, which will double the throughput of connected devices. (For the time being, PCIe 4.0 technology will be first used in conjunction with SSDs to unlock even faster data transfer speeds.)

https://www.techradar.com/reviews/amd-radeon-vii

 

Quote

In its descent from the data center, the Vega 20 GPU loses some features that will be of little use to enthusiasts. For example, Radeon Instinct accelerators using Vega 20 support both PCI Express 4.0 and coherent card-to-card communications using the Infinity Fabric interconnect, but the Radeon VII sticks to the far more common PCIe 3.0 standard and drops the data-center class inter-card connection.

https://techreport.com/review/34453/amd-radeon-vii-graphics-card-reviewed

 

 

Couple more examples above. TPU also list it as 3.0.

[leadeater]

Just now, porina said:

Couple more examples above. TPU also list it as 3.0.

Which is why I thought it was common knowledge and everyone just forgot. It's not actually an important spec of the card and it doesn't need it either, nice to have not a need to have. MI50 it's a bit more of a need to have because it's far more common to have 4-8 in a single server so being able to allocate fewer 4.0 lanes helps.

[porina]

4 minutes ago, leadeater said:

MI50 it's a bit more of a need to have because it's far more common to have 4-8 in a single server so being able to allocate fewer 4.0 lanes helps.

I hadn't thought of it that way, but with the right server CPU configuration they probably wouldn't have to go too low. I thought a use case might be that some data sets would still be too large to fit on card, so more BW to system ram would help there. (edit: if they aren't already using some fancier interconnect)

[leadeater]

1 minute ago, porina said:

I hadn't thought of it that way, but with the right server CPU configuration they probably wouldn't have to go too low. I thought a use case might be that some data sets would still be too large to fit on card, so more BW to system ram would help there. (edit: if they aren't already using some fancier interconnect)

We actually have a server that takes 16 GPUs, pretty crazy. It can't take 16 top of the line super power hungry ones as it's not designed for that, it's got 16 Tesla P4's in it but it's still crazy to see. Every time I open the chassis I still go "damn that's a lot of GPUs" lol.

[Drak3]

1 minute ago, porina said:

https://www.techradar.com/reviews/amd-radeon-vii

 

https://techreport.com/review/34453/amd-radeon-vii-graphics-card-reviewed

 

 

Couple more examples above. TPU also list it as 3.0.

 

46 minutes ago, leadeater said:

That information came from AMD. Yes AMD's product page doesn't mention it, it doesn't mention PCIe specs at all. Radeon VII does not have PCIe 4.0, that information was given out in the reviewers information packs. If it were incorrect AMD would have required this information to be corrected.

 

https://www.tomshardware.com/reviews/amd-radeon-vii-vega-20-7nm,5977.html

 

They aren't just making it up.

 

Edit:

https://www.techradar.com/au/reviews/amd-radeon-vii

 

https://www.techspot.com/review/1789-amd-radeon-vii/

Still have the same issue with all of those articles.

 

Wouldn't be the first time for multiple articles to make the same mistake if they're just following the first article.

[leadeater]

35 minutes ago, Drak3 said:

Still have the same issue with all of those articles.

 

Wouldn't be the first time for multiple articles to make the same mistake if they're just following the first article.

Well I guess lead a horse to water applies then. 100% does not have PCIe 4.0, whether you believe that or not is I have to say weird.

 

If were not correct at least one would have corrected this 'mistake', AMD asked a total of zero to do this? Or did everyone they ask to correct the information ignore that request? None of them cared about their credibility, for such a thing so easily disproved?

 

Edit:

Plus I guess the product spec sheet from manufacturers of the cards could be incorrect too?

https://www.gigabyte.com/Graphics-Card/GV-RVEGA20-16GD-B#sp

 

https://www.sapphiretech.com/en/consumer/212910140g-sapphire-radeon-vii-16g-hbm2-hdmi

 

[.Apex.]

17 minutes ago, leadeater said:

Plus I guess the product spec sheet from manufacturers of the cards could be incorrect too?

[S w a t s o n]

There's no chance they are gonna support PCIe 4 on the old boards. They were having trouble getting the new x570 boards to support PCIe 4 properly and that's not even what caused the chipset to need a fan. (Gonna be NVMe RAID on PCIe 4.0 drives that can saturate the bandwidth fully)

 

 

[Nicnac]

Oh boi can’t wait to get a nice used zen 2 setup when zen 3 drops

[Drak3]

2 minutes ago, leadeater said:

AMD asked a total of zero to do this? 

AMD also doesn't list PCIe revision, so I'm under the impression that it's artificially locked and that status is subject to change.

[The Benjamins]

44 minutes ago, leadeater said:

Well I guess lead a horse to water applies then. 100% does not have PCIe 4.0, whether you believe that or not is I have to say weird.

 

If were not correct at least one would have corrected this 'mistake', AMD asked a total of zero to do this? Or did everyone they ask to correct the information ignore that request? None of them cared about their credibility, for such a thing so easily disproved?

 

Edit:

Plus I guess the product spec sheet from manufacturers of the cards could be incorrect too?

PIC

https://www.gigabyte.com/Graphics-Card/GV-RVEGA20-16GD-B#sp

 

PIC

https://www.sapphiretech.com/en/consumer/212910140g-sapphire-radeon-vii-16g-hbm2-hdmi

 

The MI60 which is what the Radeon VII is based off is PCIe Gen 4.0

https://www.amd.com/en/products/professional-graphics/instinct-mi60

[leadeater]

14 minutes ago, Drak3 said:

AMD also doesn't list PCIe revision, so I'm under the impression that it's artificially locked and that status is subject to change.

Yes it will just be firmware, the GPU die is no different but the likelihood it'll get enabled later is very low. None of the cards went through the PCIe 4.0 spec certification (cost saving) and they don't actually need a PCIe 4.0 interface. The bandwidth would go unutilized and motherboards are not going to forgo x16 slots because PCIe 4.0 exists and nothing needs that bandwidth (yet). Every gaming graphics card on the market today is PCIe 3.0 with x16 connectors so every motherboard with PCIe 4.0 support will have x16 slots to keep compatibility physically and electrically with these cards.

 

There is no big change coming with how lanes are allocated on motherboards from the CPU.

 

It's a do nothing feature for gaming systems, in regards to graphics cards. Chipsets and other I/O is another story, highly useful there.

[leadeater]

10 minutes ago, The Benjamins said:

The MI60 which is what the Radeon VII is based off is PCIe Gen 4.0

https://www.amd.com/en/products/professional-graphics/instinct-mi60

Yes I know that, it's mentioned in the quotes. That's why it was important to point out that it does not feature PCIe 4.0, I don't mean by me I mean the reviewers who all got official information packs from AMD which either would have contained that information or they would have asked.

 

To certify a card as PCIe 4.0 probably costs a decent amount more than PCIe 3.0 and if there is no reason to do it then just don't. Edit: Plus it's not just AMD that has to certify it, through reference board designs, each AIB would have to. It's rather likely most of them are not geared up for PCIe 4.0 yet.

[The Benjamins]

Just now, leadeater said:

Yes I know that, it's mentioned in the quotes. That's why it was important to point out that it does not feature PCIe 4.0, I don't mean by mean I mean the reviewers who all got official information packs from AMD which either would have contained that information or they would have asked.

 

To certify a card as PCIe 4.0 probably costs a decent amount more than PCIe 3.0 and if there is no reason to do it then just don't.

fair point, GPUs don't need PCIe 4.0 much unless we want to use it at x8 so we have mroe lanes for other GPUs and/or NVME drives.

PCIe 4.0 x4 Drives are expected to be at computex, with speeds 5000MBpes +

[Trixanity]

2 hours ago, leadeater said:

Yes I know that, it's mentioned in the quotes. That's why it was important to point out that it does not feature PCIe 4.0, I don't mean by me I mean the reviewers who all got official information packs from AMD which either would have contained that information or they would have asked.

 

To certify a card as PCIe 4.0 probably costs a decent amount more than PCIe 3.0 and if there is no reason to do it then just don't. Edit: Plus it's not just AMD that has to certify it, through reference board designs, each AIB would have to. It's rather likely most of them are not geared up for PCIe 4.0 yet.

I'm quite sure the Anandtech article was initially filled with errors precisely because they made assumptions based on the spec of the Instinct cards but they asked AMD for clarification and that's how we ended up with the correct table which you linked in your reply.

That's at least how I recall it.

[porina]

1 hour ago, Trixanity said:

I'm quite sure the Anandtech article was initially filled with errors precisely because they made assumptions based on the spec of the Instinct cards but they asked AMD for clarification and that's how we ended up with the correct table which you linked in your reply.

That's at least how I recall it.

From memory the biggest question no one had a good answer to for a while was the exact FP64 rate, which did get settled eventually. Given all the attention it had at the time with people analysing every detail, we can be as confident as we can be that what remains is correct.

[DeScruff]

11 hours ago, Trixanity said:

Of course. They can't retroactively change the chipset so it'll be a bottleneck in that regard but I would assume any new customers would go for 500 series chipsets anyway.

Pretty much, unless there is a good sale - which is bound to happen.
I'd take a higher tier "Last Gen" board, over a lower tiered current Gen board, if they were the same price.

[Trixanity]

10 hours ago, Sypran said:

Pretty much, unless there is a good sale - which is bound to happen.
I'd take a higher tier "Last Gen" board, over a lower tiered current Gen board, if they were the same price.

I'd agree to a certain extent but in this case it seems there are substantial upgrades to the capabilities of the chipset (I'm not even taking into account PCIe 4.0) so I wouldn't even entertain the idea of a non-500 series unless the price difference was huge. Subject to change in the event that it's just more of the same obviously.

[leadeater]

30 minutes ago, Trixanity said:

I'd agree to a certain extent but in this case it seems there are substantial upgrades to the capabilities of the chipset (I'm not even taking into account PCIe 4.0) so I wouldn't even entertain the idea of a non-500 series unless the price difference was huge. Subject to change in the event that it's just more of the same obviously.

If all you do is game so just need a CPU, GPU and an SSD I don't really see 500 series offering much over 400. I like over the top configurations but it doesn't do anything in regards to performance or really usability experience at all. When RGB starts adding to FPS then the extra feature of a chipset over another might start to matter more .

 

Above not counting chipsets that do not allow overclocking.

[Trixanity]

1 minute ago, leadeater said:

If all you do is game so just need a CPU, GPU and an SSD I don't really see 500 series offering much over 400. I like over the top configurations but it doesn't do anything in regards to performance or really usability experience at all. When RGB starts adding to FPS then the extra feature of a chipset over another might start to matter more .

 

Above not counting chipsets that do not allow overclocking.

I've generally not seen any worthwhile discounts between generations so I can't imagine there being any significant price difference unless the chipset and/or boards are just that much more expensive to make. As I said it'd need to be a big discount for it to be worth it for me. I don't expect that at all. At least not in my neck of the woods. So if there isn't much of a price difference why save pennies to get an older board with (probably) limited support and a worse feature set?

 

I do agree that most people don't need the capabilities anyway but who knows when you need to add an extra m.2 SSD? Likewise many people don't need more than an mini-ITX board but they still buy full ATX anyway for whatever reason.

[leadeater]

19 minutes ago, Trixanity said:

I do agree that most people don't need the capabilities anyway but who knows when you need to add an extra m.2 SSD?

Well it's not like you actually notice the performance difference of an SSD off the CPU vs chipset either, you can see it in benchmark software though. But yea overall 400 would have to be a lot cheaper than 500 to not go for the new one.