CPU Tests
It's clear that Core i9-9900KS will be marginally faster than the 'K' version in all benchmarks. The difference ought to be more pronounced as more cores are added to the mix, as while the 9900K is able to opportunistically boost to 5.0GHz on up to two cores, it drops down to 4.7GHz when all threads are tasked.
Core i9-9900KS is 26 per cent faster than rival Ryzen 9 3900X in the low-load PiFast test. It is, however, between 25-38 per cent slower when the going gets really tough. Most of that deficit has to do with AMD throwing more cores and threads at the computation in hand.
The difference between the two 9900-series processors is pretty small, which is wholly expected.