Nvidia claims that ‘in our own internal testing, boards are able to hit speeds of 2GHz' and to our pleasant surprise this claim was easily validated.
In the above overclocked configuration actual clock speeds were consistently above the 2000 MHz mark and occasionally boosted as high as 2075 MHz.
The real-world gain of the GTX 1060 overclock we plugged in was around 11 % – hardly earth-shattering but third-party versions may well be able to clock further with higher quality VRMs and better cooling solutions.