List of Motherboards with 4 PCI-Express x16 Slots

Product Overview · This PCIe x1 to PCIe x16 Slot Extension adapter provides enhanced compatibility between motherboards and a variety of PCI-Express expansion

PCIe PCIe x 16 Slots 7 · 6 · 5 · 4 · 3 · 2 · 1 SSD Slots 5 x EZ-Latch：PCIe Slot with Quick Release Design; Fast Networks：GbE LAN & Wi-Fi

pcie slot splitter Also I forgot to say before I went to bed last night since it works as it should in the second PCIE x16 slot I would replace the Motherboard

pcie x 16 slot ‌PCIe X16 Golden Edge to PCIe X16 Slot Adapter Features : PCIe x16 card edge PCIe x16 slot PCIe Gen 3 16 lanes signals of PCIe designated 4 Layer PCB