Intel's lane counts in marketing materials are close to nonsense. Filled with dumb stuff like double counting lanes.
The processor should always have 16x lanes, these go to one or two graphics card slots. Literally everything else hangs off the chipset which is all smooshed through a ~4x PCI-e 3.0 DMI link. Which is why dual m.2 slots onboard Intel platforms are of dubious usefulness.
You say you installed it in a PCI-e 16 slot, but you also say you have a GTX 1080. I'm inferring from here but I suspect your GTX 1080 is installed in your main CPU supplied 16x slot and your second "16" slot is a 16x physical, 4x electrical...which also is pushed over the chipset. Given you also say you have 5(!) SSD drives, I suspect the DMI link is just completely overloaded, especially if any of those SSDs are m.2.
No Intel chipset for that CPU will solve this, but if you bought one with 8x/8x pci-e 16x slots you could at least use this device without it competing with limited DMI bandwidth, at the expensive of reducing the available lanes used by your GPU.