An Intel Core i9-7900X review appeared on Hexus.net. The Core i9-7900X have achieved 4.7 GHz on all ten cores with only 1.25 V, but it reached up nearly 100°C in Cinebench at that voltage.
The review was mostly positive, though they found that the performance per watt not have improved much if at all, criticized the high price tag, and Hexus.net had the following to say about the overall experience:
“X299 motherboards don’t appear to be quite ready, there are question marks surrounding the Skylake-X processors due later this year, and at the lower end of the Core X spectrum, Kaby Lake-X is nothing short of puzzling.”
You can read the full review here.