AMD: Pre-X570 boards will not support PCIe Gen 4
Yes, that's what he said. Actually, AMD's Robert Hallock said that on Reddit. earlier on some motherboard manufacturers showed PCIe Gen 4.0 support in series 400 BIOSes.
And that confirms it plain and simple. The new 500 series chipset will support PCIe express Gen 4.0 in combination with Ryzern 3000 processors. Anything below, simply not. Whether or not you'll find PCIe 4.0 a buying feature is also topic of debate, your GPU certainly will not need that bandwidth, and while PCIe Gen 4.0 based NVMe SSD(s) are fun, would you truly really need 5000 MB/sec in SSD performance, other than for bragging rights of course .
"Hallock: This is an error we are correcting. Pre-X570 boards will not support PCIe Gen 4. There's no guarantee that older motherboards can reliably run the more stringent signaling requirements of Gen4, and we simply cannot have a mix of "yes, no, maybe" in the market for all the older motherboards. The potential for confusion is too high. When final BIOSes are released for 3rd Gen Ryzen (AGESA 1000+), Gen4 will not be an option anymore. We wish we could've enabled this backwards, but the risk is too great."
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PCIe Version | Line Code | Transfer Rate | x1 Bandwidth | x4 | x8 | x16 |
1.0 | 8b/10b | 2.5 GT/s | 250 MB/s | 1 GB/s | 2 GB/s | 4 GB/s |
2.0 | 8b/10b | 5 GT/s | 500 MB/s | 2 GB/s | 4 GB/s | 8 GB/s |
3.0 | 128b/130b | 8 GT/s | 984.6 MB/s | 3.938 GB/s | 7.877 GB/s | 15.754 GB/s |
4.0 | 128b/130b | 16 GT/s | 1.969 GB/s | 7.877 GB/s | 15.754 GB/s | 31.508 GB/s |
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I think that was a fair statement by AMD. It might not be the answer customers want to hear, but it's better than AMD's reputation accidentally getting tarnished because of cheaply made mobos.
I doubt that signaling is an issue on such short distance. Linus did test PCIe 3.0 extension cable after extension cable and reached like 4 or six meters on PCIe 3.0 before he run into issue.
Sad, it would be nice to have PCIe 4.0 between 1st slot GPU and CPU on my quality x470 board. Nice, but unnecessary.
Yeah, I would've expected at the very least that the primary x16 slot feeding straight from the CPU would retain 4.0 specs. Isn't it mostly just a direct connection? Surely the signal quality couldn't diminish that much.
I would hope at least some brands, such as Asus, would allow for an experimental feature, where by default it uses 3.0 but you have the option to override it.
Not sure how this is important. Even current PCIE 3.0 the most bandwidth used are from NVME drives or just PCIE drives and they definitely do use that bandwidth but it's not like we have a number of PCIE 4 enabled drives yet.
Isn't that big of a chicken and egg problem? There aren't going to be any PCIe 4.0 devices if there are no boards to support them. One of the appeals of the AM4 platform is its long-term support.
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Sound like they force us to buy x570 mobo's, I know there are some x370 and x470 can run PCIe 4.0 but all vendors want to sell x570 as much they can profit it.
If you have x370, maybe good upgrade to x570.
If you have x470, maybe good upgrade to x670 in the future.
(Bios mod might be able enabled PCIe 4.0 anyhow) Keep eyes on that someone dare it.
2 cents.
If testing shows no performance loss on x370 my x370 motherboard will have a Ryzen 3000 slapped into with no other upgrades. Since first gen Ryzen didn't OC all that well there are a ton of us sitting on those 1700x chips that Ryzen 3700x would be a huge upgrade especially value wise if it can OC decently well.
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Well, there will be some performance loss if you count XFR (even X470 has improvements there), and depending on what your board is, the VRM might limit your OC. But I assume you overclock, and chances are your X370 will have a "good enough" VRM. Since we're probably not going to see any GPUs that'll saturate PCIe 3.0 @ x16 any time soon, it's very likely you won't have any performance loss.
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I don't think so. Pre-x470 boards aren't supposed to support PCIe 4.0, so there's no need to offer support for such a functionality. Every mobo model needs its own bios release anyway, so a manufacturer could check some of their models to see if the first 16x port seems to work with PCIe 4.0. If it seems to, make the bios switch visible. Add a warning to it, perhaps.
However, like I said, I don't see why they would do such a thing from a practical point of view since it could rob them of some new sales. I might even believe they have had some talks about this with AMD, to see what sort of incentives each generation would offer, to balance the CPU compatibility remaining there, as opposed to Intel's scheme. So far the generations have had at least something little. PCIe 4.0 might be the main thing for x570. It would certainly be more visible in marketing than x470's benefit over x370.
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but that's the brilliance of this move - they paid Phison for a new ssd controller for pcie 4.0 and they have (rt now) four suppliers of pcie 4.0 storage.
as gamers most of us shrug this off...but if you're a "content creator" dealing with massive files, a pcie 4.0 m.2 or slot ssd is worth the money from day one.
and with Ryzen 2 supporting 40 lanes of pcie 4.0, there are plenty of professional applications to take advantage of the bandwidth already.