I have two different PCIE USB 3.0 cards (one Inateck Fresco and the other , and neither of them will work in the top X1_1 or the X1_3 slot.
PCIE slot X8_1 is populated with a functioning 1080Ti, which blocks X1_2 from being used at all.
The inateck PCIE USB 3.0 card works fine in the X8_2 slot.
To eliminate BIOS updates as a possible issue, I just upgraded to Bios 3504 to see if that would fix anything, but nothing seems to have changed.
Any idea what the issue is here? Maybe a BIOS setting I haven't looked at, perhaps?
