You won't be able to use a PCIe 4.0 SSD on your existing motherboard

[Windows Central]

Best answer: Officially, no. The new X570 chipset for AMD Ryzen systems is currently the only confirmed way to use a PCIe 4.0 SSD at its full performance. For everyone else, our best recommendation is currently the Samsung 970 EVO Plus.
Blazing speed: Samsung 970 EVO Plus (From $80 at Amazon)
[h=3]AMD's X570 chipset required[/h]PCIe 4.0 is a standard, but so far the only confirmed way to make use of it is on AMD's X570 platform. This was announced at Computex 2019 alongside the new Ryzen 3000 processors.

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