PCI Express x8 Dual Copper Port 10 Gigabit Server Adapter (Intel X540 Based)
Amazon.com: ADT-LINK PCIe X8 to X8 Adapter Cable for Graphics Video Card PCI Express Extender PCIe X8 to PCIe X8 Slot Extension Cable for 1U 2U Server (80CM) : Electronics
PCIe Gen4 x8 to x16 Adapter - Serial Cables
Pci Express 3.0 X8 To M.2 Nvme Extension Cable Nvme To Pcie 8x Cable Graphics Card Riser Adapter - Pc Hardware Cables & Adapters - AliExpress
Expansion Backplane, 2 PCIe x4 & 1 PCIe x8 slots (436) - One Stop Systems