PCIEx16 drops to x 8 when M2 SSD is installed???

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PCI Express expansion slot of industrial computer, PCI Express cards Physical shape, Signal , x1, x4, x8, x16 x1, x1, ◎, ×, ×, × x4, x1, ◎

Concept Product CP074-2 8 x NVMe SSD to PCIe x16 Mobile Rack Adapter Card for PCIe Expansion Slot with PCIe Bifurcation Function  Expansion Slots ITFreeTraining•34K views · 10:39 Go to channel · I Will PCIe x1 x4 cards

what is a slot cornerback PCI Express expansion slot of industrial computer, PCI Express cards Physical shape, Signal , x1, x4, x8, x16 x1, x1, ◎, ×, ×, × x4, x1, ◎ expansion cards, allowing you to install a PCIe card in an x1 slot The PCI Express x1 to x16 adapter accommodates low profile x2, x4, x8, x12 or x16