CP074-1_4 x NVMe SSD to PCIe x16 Mobile Rack

pcie x16 expansion slot   Dan pcie training error slot 1

20mm Spaced Slots:The 20mm slot spacing allows for easy installation and compatibility with PCIE extension cable adapters Computer Expansion SlotU 2 PciePCIe

In ASUS 「PCIe x16 Slots - 7」 Supported expansion board 1 PCIe FlexibleLOM HL, FH FlexibleLOM x16 x8 16, 8, 4, 1 Four-port 1 GB NIC card SSD enablement board 2 PCIe

the feed slot cover of the rear tray is open hello everyone, I need a motherboard with at least 4 x16 pciei, i dont care about about pcie version I need to install four 10 gigabit pcie card  Is it possible? I don't seem to find any PCIe expansion solution that expands a single PCIe3x16 slot to multiple such slots, that also supports