Robert built his own computer with a nice Gigabyte motherboard, but his USB 3 video card isn't working with it. Leo says that's likely because his third-party card doesn't want to use the USB 3 chip on the motherboard. It has it's own. When he plugs the card into his PCI-Express slot, he should make sure it's properly seated and is a 4 lane slot. If Windows doesn't recognize it, then he should make sure the PCI-Express slot is enabled. He can refer to his motherboard manual on how. Also, he should check in the Windows 10 device manager to see if there's an "X" on the USB hub. That means there's a missing driver. Unfortunately, this is the downside of building his own computer. Everyone wants to pass the buck.
The chatroom says to go into the BIOS/EFI Setup and disable the motherboard's USB 3 chip. There could be a conflict.