Latest version of Speccy says my PCIEX16/X8_1 slot (Slot 1) is not in use, and shows two PCI-E x1 slots (slots 0 and 2) in use instead. My GPU is in that X16/X8_1 slot right now.
My motherboard is Asus Maximus VII Ranger with latest BIOS, and my GPU is Asus GTX 660 DirectCU II OC.