Sources claim that a few Ryzen 3000-series CPU samples have arrived at Radeon Technologies Group in order to tune the GPU drivers for the new interconnects. Tests have revealed that the upcoming CPUs are faster than the i7-8700K from Intel, but are very unstable and crash very often at the moment.
https://www.notebookcheck.net/AMD-Ryzen-3000-series-7-nm-CPUs-already-tested-internally.336562.0.html