MP 7,1 PCIe 4.0 NVMe SSD in ASM2824/PLX8747 (like a Sonnet M.2 4x4) speed?

[flyingmanatee]

Has any tried a PCIe 4.0 SSD in a ASM2824 / PLX8747 in a 7,1 with a PCIe 4.0 SSD? In the Mac Pro 3,1-5,1, they enable the ability to address more lanes and thus go beyond PCIe 2.0 speeds. Does this apply to the Mac Pro 2019s?

 

[joevt]

Has any tried a PCIe 4.0 SSD in a ASM2824 / PLX8747 in a 7,1 with a PCIe 4.0 SSD? In the Mac Pro 3,1-5,1, they enable the ability to address more lanes and thus go beyond PCIe 2.0 speeds. Does this apply to the Mac Pro 2019s?

ASM2824 / PLX8747 are PCIe 3.0 switches. In a Mac Pro 3,1-5,1 they can move data between the slow (PCIe 2.0) & wide (x16) slot and the fast (PCIe 3.0) and narrow (x4) NVMe SSD without loss in performance for the NVMe. Without the PCIe switch, the NVMe would be limited to the PCIe 2.0 speed of the slot.

Since they are PCIe 3.0 switches, they do not add any benefit for a PCIe 4.0 NVMe in the Mac Pro 7,1 which has PCIe 3.0 slots, except they do allow connecting more than one NVMe to a slot.

If you want PCIe 4.0 NVMe speed in a Mac Pro 7,1 then you need a PCIe card with a PCIe 4.0 switch such as the HighPoint SSD7505.
https://forums.macrumors.com/threads/pcie-ssds-nvme-ahci.2146725/