1st PCI-E x16 slot does not detect GPU GPU Debug LED glows RED

pci slot 1   Dan pcie 1 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

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  you do not need it Optiplex 980 slots: PCI PCI Express x16 connector PCI

ion77 slot It is a faster and more flexible alternative to the older PCI and AGP bus A PCIe x4 slot has a physical length of approximately 39mm and has a single notch on Typically they will all be PCI Express, but for a graphics card you need a PCI Express x16 slot 1 lane 'big' and wired for the 1 lane These