Much of the attention over Intel's recently launched 9th generation Core lineup has been paid to the Core i9-9900K, the flagship CPU in the new mainstream lineup, and Intel's first 8-core/16-thread part. However, there are two other 9th gen chips: Core i7-9700K and Core i5-9600K. Review embargoes exist for all three, though benchmarks have leaked out showing how the Core i5-9600K performs at stock settings, and when overclocked to 5.2GHz.
Like the two other 9th gen parts, the Core i5-9600K is built on a refined 14nm++ manufacturing process. It's the lone 6-core part in the new lineup and lacks Hyper Threading support. It has a 3.7GHz base clock and 4.6GHz boost clock, and 9MB of L3 cache. Perhaps importantly for overclockers, it also features a solder TIM (thermal interface material) underneath the IHS (integrated heatspreader) instead of the lower quality grease that Intel switched to a few generations ago.
A video in China purportedly shows the Core i5-9600K being tested in an MSI Z390 MEG Godlike motherboard with 16GB of DDR4 memory and a rather large air cooler, Thermalright's Silver Arrow Extreme. Under that setup, the Core i5-9600K was able to run at 5.2GHz, albeit with a high 1.507V setting.
The testers did not run any gaming benchmarks, so those will have to wait for another day. However, they did run a few CPU intensive benchmarks. In Cinebench R15, the Core i5-9600K scored 1,034 CB at stock settings, and 1,207 CB when overclocked. That's about in line with a Core i5-8400, a 6-core/6-thread part clocked at 2.8GHz to 4GHz, which in our tests scores 953 at stock settings.
Cinebench R15 is a benchmark that scales well with additional cores and threads. As such, the lack of Hyper Threading support on the Core i5-9600K appears to hold it back compared to processors like the Core i7-8700K, which we benchmarked at 1,425 CB.
For the moment, the Core i5-9600K is the least expensive 9th gen chip. Intel set the price at $262 for 1,000-unit trays (bulk orders, basically), and it's available to pre-order for $279.99. That's a $75 premium over the previous generation Core i5-8400, which sells for $204.99.