It should do, the specs state that it's a pcie x16 slot that runs at x16 pcie 3.0 standard https://www.gigabyte.com/Motherboard/GA-H110M-H-DDR3-rev-10#spExpansion Slots
1 x PCI Express x16 slot, running at x16
(The PCI Express x16 slot conforms to PCI Express 3.0 standard.)
2 x PCI Express x1 slots
(All of the PCI Express x1 slots conform to PCI Express 2.0 standard.)
It maybe that the card you are currently using only runs at a max of pcie 2.0 x8 speeds which is why cpu-z etc is showing you that info.