What is the Function of PCI Slot?

If you've got a x16 slot your going to have to find the right IOU 0 or 1 port and set it to x8x8 or whatever you want Set all of them and save

PCI Express slot from the BIOS menu before switching to a PCIe video card 1 Open the BIOS menu Pressing the “F2” or the “Del” key during computer startup

pcie 4 gpu in pcie 3 slot DescriptionPci Express English: PCI -PCI Express -PCI Express 16 1 x PCIe x16; 2 x PCIe x1; 1 x PCI Date, 17 June 2013

pcie nvme slot 1 8+4 Solid Pin CPU Power Connector ; 2 Twin 14+2+1 Digital VRM Design ; 3 Advanced Thermal Design ; 4 Design Ready for PCI Express ; 5 EZ-Latch