Try disabling "Cache custom textures on GPU". The Xenoblade custom texture pack is VERY big and 3GB VRAM won't be enough to cache all the textures to it. If you're using the DDS (not PNG) version of the pack, you might not even see a difference with it disabled.
Intel i5-4690k (Devil's Canyon) @ 3.5 GHz (+Scythe Mugen) / Gainward GTX 1070 Phoenix (OC'd) / ASUS Z97 PRO GAMER / 16GB G.Skill DDR3-2400 CL10 TridentX / X-Fi XtremeMusic / Win10 Pro 64bit / Dell S2716DG Monitor / 3x original WiiMote+MotionPlus+Nunchuk

