Hi , thanks for the reply.
As I mentioned I tried both the smaller and larger PCIE slots.
There is nothing in the BIOS to change the slots from gen 2 to gen 3. According to the specs, I think that they are all gen 3.
https://www.gigabyte.com/au/Motherboard/B360-AORUS-GAMING-3-rev-10#sp
2 x PCI Express x1 slots (PCIEX1_1, PCIEX1_2)(All of the PCI Express slots conform to PCI Express 3.0 standard.)
Another thing I noticed is that in the BIOS, the PCIE Slots are shown in the Plug In Devices Info section. Only the graphics card (PCIEX16) is shown, 1_1,1_2, and 1_3 are all N/A. Saying that, the wifi is in slot 1_4 which isn't shown in the list at all so I'm not sure what that means.
https://imgur.com/a/jM1ZguB