The usual disclaimer applies—there is only so much we can garner from a leaked benchmark, for a variety of reasons. Even assuming everything is legit, a single benchmark run falls well short of painting a complete picture. Nonetheless, we can only work with what is out there, and right now that's a 3Mark Time Spy run.
Here is the benchmark entry...
The CPU score is the value that is of interest here, as the Overall and Graphics scores lean heavily on the GPU. As shown in this particular benchmark run, the Core i9-10900KF posted a CPU score of 12,412. That is not very meaningful in a vacuum, though fortunately, 3DMark's database is fleshed out with plenty of other CPUs to compare against.
The Ryzen 9 3900X is a 12-core/24-thread CPU with a 3.8GHz base clock and 4.6GHz max boost clock. It also features 64MB of L3 cache.
Faster memory benefits AMD's processors more than it does Intel's chips, and the above comparison shows the Ryzen 9 3900X paired with DDR4-3200, DDR4-3400, and DDR4-3800MHz memory. Intel's Core i9-10900KF with DDR4-2666 memory managed to outpace the Ryzen 9 3900X with DDR4-3200 RAM. When paired with DDR4-3400 memory the Ryzen 9 3900X slipped ahead, then drew a larger margin of victory with DDR4-3800 memory.
The scores are relatively close across the board. That's impressive at a glance, given the core/thread disparity, though Intel's chip appears to be benefiting from a faster boost frequency.