It appears that Intel has leaked a partial list of their 9th gen Core CPUs, as well as a detailed breakdown of their specs. A series of previously unannounced Core i3 and Core i5 processors were released on a Microcode Revision Guidance document, which has since been reworked to remove the reference to 9th gen products.
Because the new CPUs were listed under the Coffee Lake category, it is unclear if this means the new CPUs are 8th gen CPUs or if they simply did not add the new code name to the document. The confusion around which generation these CPUs are is not helped by the fact that Intel itself has specific in their own documentation that the number 9 at the beginning of the CPU title should be the Gen Indicator.
The leaked CPUs are Core i3-9000, Core i3-9100, Core i5-9400, Core i5-9400T, Core i5-9500, Core i5-9600, and the Core i5-9600K. The omission of any new Core i7 processors is likely because they would have been listed in a different section where they did not replicate the same copy-paste error.
If one leak wasn’t enough, another document was leaked, and then removed by Intel. The original version of the document, called “8th Gen Core Family Spec Update”, included the previously mentioned 9000 CPUs. Thankfully VideoCardz captured the document before it was removed. This leads to further speculation on whether these new CPUs are 9th or 8th gen.
The document outlines all the major specs of each CPU, including the fact that the frequency can boost an additional 200MHz in Max turbo state compared to last gen. It can accomplish this boost while maintaining the same TDP of the previous gen as well.
Most of the base clock speeds are almost identical when comparing the new and old gen CPUs, but the Core-i5 9600K, Core i5 9400, Core i3 9100, and Core i3 9000, are each 0.1GHz faster than their previous gen counterpart.