3DMark Fire Strike
3DMark is the latest version of this hugely-popular synthetic benchmark. Making use of DX11 features such as tessellation, compute shaders and multi-threading, it provides modern-day results and is available as a free download.
It's hard to tell the difference between the stock GTX 1080 Ti and a Titan X, but Inno3D's X3 is a different kettle of fish. Armed with higher frequencies and able to stretch its legs courtesy of a beefy cooler, it has no problem topping the charts and ekes out a healthy lead at the higher resolutions.