The OS will be a linux, I want ton make this computer a NAS server, so I will use Debian 9 tihnk so...
Did you know how to set up all the PCI to legacy mode?
I forced to 2.0 from 3.0 and didn´t work.
I installed a PCI-e 1X ethernet card in the 16x slot and worked, the problem is with this card. The card is working fine in another mother with x8 slot, need to test in a x16 slot yet.