OK, let me ask other thing them: what kind of power is safe to estimate for a overclock Tegra X1?
At FP32, a X1 have 0,5 TFlops. At FP16 it have the double. Overclocking can give a 1 TFlops at FP32?
If you want reliable overclocks, an increase of 100% is not likely, think more like 10-15%.
Also remember that the Shield TV has a fan in it too, so it's entirely possible the dev kits aren't overclocked, just setup to be very reliable, or using off the shelf fans.
No, you're just being extremely pessimistic. First of all, I said that this was a best case which means that I was intentionally being optimistic (though not anywhere near "extremely"). Second, there's absolutely nothing out of the question about those clocks on 16nmFF unless you're going to use the "it's Nintendo" argument. The Pixel C has an X1 clocked at 850MHz and a 10.2-inch, 2560x1800 screen. NX with a much smaller screen at 720p or even 540p and a 16nm Pascal Tegra might use around a third of the 14W that the Pixel C uses with the GPU at 700MHz. I'd say that 500MHz is the absolute minimum. Any less doesn't really make sense at all, and 200MHz is just kinda silly. Apple can get a 450MHz GPU into a 7mm thin phone, but Nintendo is limited to 233MHz optimistically in something likely twice as thick? Ehhhhhhhhhhh...
Call me pessimistic too then, when dealing with Nintendo, I like to bet on the weaker side.
You quote "specs" of phones, but remember that phones do not run 100% clocks all the time, in fact when in gaming, and other intensive operations, often the GPU clocks are throttled back due to thermal throttling, since the heat generated is too much for passive cooling, not to mention that battery life is hugely affected.
If nintendo is making a dedicated gaming handheld, they would likely want the clocks to remain steady and predictable, so thermal throttling will be avoided. How will they do that? Likely by reducing the maximum clock speeds.
This has been covered many times even in the Eurogamer thread; the fact that the X1s in the devkit are active cooled and have loud fans implies that they're being overclocked, which in turn implies that they are placeholders for something more advanced.
It was speculation that it was overclocked, based on there being a fan. There was never any confirmation. Remember the shield TV also has a fan in it.