They'll fit without issue. The typical GTX 970 are dual-slot widths; meaning they take up two expansion slots. These Zotac AMP cards appear to be slightly wider, but no where near triple-slot width cards. There are two expansion slot widths between that motherboard's PCI-Ex16 3.0 slots. So while you will likely lose usage of all your PCI-Ex1 slots, there will still be room between the two cards when installed into the PCI-Ex16 3.0 slots.
-Wolf sends