NVIDIA chose to limit the release of their GTX 1070 Ti to reference cards, all sporting the same clocks regardless of the model.  That does not mean that the manufacturers skimped on the features which help you overclock successfully.  As a perfect example, the MSI GTX 1070 Ti GAMING TITANIUM was built with Hi-C CAPs, Super Ferrite Chokes, and Japanese Solid Caps and 10-phase PWM.  This resulted in an impressive overclock of 2050MHz on the GPU and a memory frequency of 9GHz once [H]ard|OCP boosted the power delivered to the card.  That boost is enough to meet or even exceed the performance of a stock GTX 1080 or Vega 64 in most of the games they tested.

"NVIDIA is launching the GeForce GTX 1070 Ti today, and we’ve got a custom retail MSI GeForce GTX 1070 Ti GAMING TITANIUM video card to test and overclock, yes overclock, to the max. We’ll make comparisons against GTX 1080/1070, AMD Radeon RX Vega 64 and 56 for a complete review."

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