AMD may want to be concerned. Based on alleged Time Spy benchmark results shared by hardware leaker @_rogame (opens in new tab), the AMD Ryzen 9 3900X (opens in new tab)will have a strong rival in the upcoming Intel Core i9-10900KF.
The i9-10900KF is one of Intel's forthcoming Comet Lake desktop chips (opens in new tab) and will compete with AMD's recently launched Ryzen 3000-series (codename Matisse) CPUs (opens in new tab). More specifically, the i9-10900KF will be trading blows with the Ryzen 9 3900X, which makes today's fight so interesting.
As a quick summary, the i9-10900KF is on Intel's 14nm node and will feature 10 cores (opens in new tab), 20 threads (opens in new tab)and 20MB of L3 cache (opens in new tab). The chip reportedly has a 3.7 GHz base clock (opens in new tab) and, thanks to Intel's Thermal Velocity Boost (TVB) feature, boost to 5.3 GHz. As dictated by the "F" suffix, the i9-10900KF is part of the breed of Comet Lake CPUs that lack integrated graphics (opens in new tab).
On the other side of the octagon, the Ryzen 9 3900X debuted on TSMC's 7nm FinFET manufacturing process and comes flexing 12 cores, 24, threads and 64MB of L3 cache. The processor clocks in with a 3.8 GHz base clock and 4.6 GHz boost clock. On paper, the i9-10900KF is already at a disadvantage with two fewer cores and significantly less L3 cache. However, it does flex higher clock speeds.
According to the Time Spy entry, the i9-10900KF had a 12,412 CPU score. The Ryzen 9 3900X, in return, scored 12,857 points. Therefore, AMD's chip is only up to 3.6% faster. In the i9-10900KF's defense, it was paired with DDR4-2400 RAM (opens in new tab), while the Ryzen 9 3900X's system was on speedier DDR4-3200 memory.
Indeed, memory speed shows a significant impact on the Time Spy benchmark. The same Ryzen 9 3900X scored 13,913 and 13,650 points with DDR4-3600 and DDR4-3800 memory, respectively.
Meanwhile, the i9-10900K, which is essentially the i9-10900KF but with an iGPU, scored 13,142 points with DDR4-2666 memory. Since the i9-10900KF is basically a replica of the i9-10900K but without integrated graphics the performance for both processors should be in the same neighborhood.
If we compare the i9-10900K DDR4-2666 result to the Ryzen 9 3900X DDR4-3200 result, Intel's processor is actually up to 2.2% faster. That's the problem with leaked benchmarks. You can never be sure of the conditions of the test system or operating system. When unreleased hardware is involved, there's always a strong chance of discrepancy between the results. Plus, this has no implications as to whether the i9-10900KF can keep up with the Ryzen 9 3900X in other real-world scenarios, especially multi-threaded ones.