While this is a 10th generation processor from Intel, it isn't built on 10nm process tech like Ice Lake. Instead, this is another refresh of Skylake-X, meaning that we're still beholden to the 14nm++ process node. With that being said, this is a 10-core/20-thread processor according to Geekbench with a base clock of 3.47GHz and a boost clock of 4.4GHz. However, momomo_us, who happened to stumble across the benchmark, says that the Core i9-10900X will have a base clock of 3.7GHz when it ships.
The Core i9-10990X will supplant the Core i9-9900X -- which is also a 10-core/20-thread processors -- in Intel's HEDT lineup. The Geekbench 4 result shows the Core i9-10900X pulling down a single-core score of 5204 and a multi-core score of 39717.
A separate leak from Bilibili suggests that the Core i9-10900X will sit at the bottom of the lineup for the incoming Cascade Lake-X family, and will be joined by the Core i9-10920X (12-core/24-thread), Core i9-10940X (14-core, 28-thread), and Core i9-10980XE (18-core/36-thread).
According to Intel, the first Cascade Lake-X processors will arrive later this month, and the company is claiming that relative performance-per-dollar will provide anywhere from a 1.74x to 2.09x uplift over Skylake-X. In addition, in its most potent configurations, Intel is claiming that Cascade Lake-X will outperform AMD's current-generation Ryzen Threadripper processors, which top out with the Ryzen Threadripper 2990WX.
Unfortunately for Intel, it looks as though AMD could drop its Zen 2-based Ryzen Threadripper 3000 processors onto the marketplace at any time. With cooler-running 7nm process tech and as many as 32 physical cores and 64 threads, early benchmarks are showing that these chips will be absolutely beastly in the HEDT market.