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chucker
 
Join Date: May 2004
Location: near Bremen, Germany
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2021-12-30, 04:12

Quote:
Originally Posted by PB PM View Post
PCI-5 is not a new thing, these drives are.
PCIe 5 is still quite new. Intel's Alder Lake (which is so far only available for high-end desktops) is the first gen to have it. AMD won't have it until next year.

And, as far as SSD production in general goes, it's absolutely the limiting factor. NVMe does up to four lanes. A PCIe 3 lane is 985 MiB/s (gross). Therefore, a PCIe 3 SSD tops out at about 3.5 GiB/s. PCIe 4 doubles all that, and a PCIe 5 doubles it again. That's why we're now seeing 7 GiB/s SSDs, and soon 14 GiB/s ones.

Quote:
Originally Posted by PB PM View Post
The real question isn't, does Apple have access to PCIe 5.0 SSDs, the question is, does the architecture for the M1/M1 Pro /M1 Max support PCIe-5.0?
So, my guess is no. M1 is PCIe 4, and I suspect they haven't upgraded that to 5 for the Pro/Max.

However, Apple doesn't appear to connect their SSDs through PCI at all. They use an NVMe-compatible protocol, but over an entirely different bus. Perhaps to further reduce latency.

So, that could mean that they might be able to take advantage of faster SSDs even though their PCIe bus is 4.0.

Quote:
Originally Posted by PB PM View Post
If not, it's irreverent. My guess is no, we won't be seeing PCI-5 on the Mac's until second or maybe generation silicon ships.
That would be my guess as well.
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