The Prime Z370-A supports keeping all three of its x16-length slots active, even when hosting two M.2 drives, which should be seen as a significant benefit by anyone who might ever consider installing two M.2 drives. Sharing problems are still present but lessened, as the second M.2 slot gets only two PCIe lanes until the user goes into firmware and sets the slot to x4 mode, which disables two of the SATA ports.

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