Several database entries of the Ryzen 7 2700X were found, with a base clock of 3.7GHz. This is an eight-core chip with sixteen threads. The Turbo clock varies a bit, sometimes it's listed as 4124MHz but there are also entries that reveal a frequency of 4200MHz. This model has a TDP of 95W. Based on these specs, the base and Turbo are at least 300MHz higher than the Ryzen 7 1700X.
Another part of the second-gen Ryzen lineup will be the Ryzen 5 2600. This six-core chip has twelve threads and a 65W TDP. The base clock is said to be 3.4GHz, with a Turbo of 3.8GHz.