There's no reason to test a GeForce GTX 1080 Ti at 1920x1080; at that resolution, even our high-end host processor bottlenecks performance. Rather, these cards are designed for 2560x1440 and up.
At QHD, the GeForce GTX 1080 Ti Lightning Z is, depending on the game, between 11 and a bit more than 13 percent faster than a GeForce GTX 1080 Ti Founders Edition or Titan X (Pascal).
At this high resolution, MSI's Lightning Z is, again, depending on the game, between nine and ~12 percent faster than Nvidia's GeForce GTX 1080 Ti Founders Edition and Titan X (Pascal).
Many of these titles are playable at 4K. Those that aren't can be made smoother by dialing down the quality settings somewhat.
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