13th Gen Core i9-13900K vs Core i5-9400F
Short answer: which is best?
13th Gen Core i9-13900K is 159.7 % stronger than Core i5-9400F. 13th Gen Core i9-13900K ranks #8 of 102 measured processors at WhatFPS (13,199 CPU score over 2 verified runs). Core i5-9400F ranks #83 of 102 measured processors at WhatFPS (5,082 CPU score over 1 verified runs). The numbers are measured in 3 verified WhatFPS runs — not estimated, not self-reported.
Measured comparison
| Metric | 13th Gen Core i9-13900K | Core i5-9400F |
|---|---|---|
| CPU score (the processor's own performance) | 13,199 | 5,082 |
| Best rig (GAMING — whole PC) | 10,782 | 4,848 |
| Integer (MT) | 12.5 Gop/s | 2.1 Gop/s |
| Single-thread (1T) | 0.88 Gop/s | 0.46 Gop/s |
| Draw calls/s (DX11) | 9,342,700 | 7,013,036 |
| Cores / threads | 24 / 32 | 6 / 6 |
| L3 cache | 36 MB | 9 MB |
Fragz' verdict
The 13th Gen Core i9-13900K is the clear winner in this showdown, leading the Core i5-9400F by a substantial 159.7% in overall CPU score. This massive performance gap is evident in its single-thread performance, hitting 0.88 Gop/s compared to the i5-9400F's 0.46 Gop/s, which directly translates to higher gaming frame rates. It also pushes significantly more draw calls per second, reaching 9,342,700 versus 7,013,036, and achieves a much higher 77.9 FPS in the Supernova DX11 test compared to the i5-9400F's 58.5 FPS. Beyond single-thread, the i9-13900K's multi-threaded integer performance is a robust 12.5 Gop/s, vastly outperforming the i5-9400F's 2.1 Gop/s, thanks to its 24 cores, 32 threads, 6119 MHz peak clock, and 36 MB of L3 cache. While the data for both CPUs comes from a very thin sample of verified runs—two for the i9 and just one for the i5—the 13th Gen Core i9-13900K is undeniably the superior chip for high-end gaming and demanding workloads, leaving the Core i5-9400F as a far more modest option.
Generated October 31, 2026 from the 3 verified runs available then. The verdict is never silently rewritten — new numbers get a new verdict.
What the numbers mean
The CPU score is the processor's own performance — that is what we rank on. GAMING is the whole rig's score in the best PC we measured the processor in, and leans heavily on the graphics card. A strong processor in a weak PC gets a low GAMING score without being worse. We show both and never mix them.
All numbers come from our benchmark suite: four hand-built 3D scenes written directly against the graphics APIs in Rust, the same load on every PC. The methodology is open at https://whatfps.com/metodik
All measurements for 13th Gen Core i9-13900K · All measurements for Core i5-9400F