PCI e slot provides power but does not recognize any cards

[aa1991aa]

So I recently built a new PC and everything is ok so far except one thing.
I have a ASUS ROG STRIX Z-370-E motherboard and one of the PCIE slots doesn't work .
When I put a new card ( sound or network card ) it powers on but windows can not detect it !
The first PCIE-1 is working fine , the graphics card is installed in the PCIE16x and is working fine then the PCIE-2 & 3 are blocked by the big GTX1080ti 😉 so I have to use PCIE-4 ( which is not working ) , What could be the issue ? any help would be appreciated !

 

[kerberos_20]

The USB 3.1 Gen2 front panel connector shares bandwidth with PCIE_x1_2 and
PCIE_x1_4.
If the USB 3.1 Gen2 front header is connected, PCIE_x1_2 and PCIE_x1_4 will
be disabled.

 

[aa1991aa]

The USB 3.1 Gen2 front panel connector shares bandwidth with PCIE_x1_2 and
PCIE_x1_4.
If the USB 3.1 Gen2 front header is connected, PCIE_x1_2 and PCIE_x1_4 will
be disabled.

Hmmm never heard of it , the PCIE-1 is working though as I said earlier !
is there any way to enable it ?
Thanks for the reply BTW

 

[kerberos_20]

its in you mainboard manuals
disable front usb 3.1 ports and it will work