Does the Core i9-13900K bottleneck the RTX 4090?
At 1440p the Core i9-13900K and RTX 4090 are evenly matched: neither part is waiting on the other for long, and you get about 191 fps in a typical modern AAA game. Full breakdown at all three resolutions below, with estimated FPS in 14 games and which part to upgrade first.
Typical modern AAA game, high settings, no upscaling, 32GB (2x16GB) DDR5-6000. Confidence: high. Data version 2026.09. How this is estimated.
Core i9-13900K + RTX 4090: change RAM, resolution or game
Data version 2026.09 · methodologyNothing is badly idle in Typical modern AAA game at 1440p. You see about 191 fps and every part is pulling its weight.
Confidence: high. Estimates from benchmark indices, not a measurement of your PC. How this works.
Cards that would still add frames
Every part is pulling its weight, so nothing here is wasted money. If you simply want more frames in Typical modern AAA game at 1440p, these are the cards that deliver them.
Affiliate link: if you buy through it we may earn a commission at no extra cost to you.Your memory is not the problem.
32GB (2x16GB) DDR5-6000 is plenty for Typical modern AAA game. Do not let anyone sell you more RAM as an fps upgrade.
Verdict: significant CPU bottleneck at 1080p, balanced at 1440p, heavily GPU-bound at 4K
At 1080p the Core i9-13900K holds the RTX 4090 back by roughly 33%. You are paying for graphics performance you cannot use at this resolution; raising settings or resolution is free performance here.
At 4K the RTX 4090 is heavily GPU-bound (53%). The Core i9-13900K has a lot of unused headroom, so a much faster graphics card would pay off without touching the processor.
The pattern is the classic one: the Core i9-13900K limits at 1080p, the RTX 4090 limits at 4K, and 1440p sits in between. If you play at 1080p on a high-refresh monitor, the processor matters more than the card here.
Core i9-13900K + RTX 4090 bottleneck at 1080p, 1440p and 4K
| Resolution | CPU ceiling | GPU ceiling | Verdict | Est. fps |
|---|---|---|---|---|
| 1080p | 211 fps | 313 fps | 33% CPU | 205 |
| 1440p | 211 fps | 191 fps | balanced | 191 |
| 4K | 211 fps | 98 fps | 53% GPU | 98 |
The ceilings are what each part could deliver alone in a typical modern AAA game. The lower one is your frame rate; the gap is the bottleneck. In 14 of 14 games the Core i9-13900K is the 1080p limiter by 10% or more.
Estimated FPS: Core i9-13900K with RTX 4090 in 14 games
| Game | 1080p | 1440p | 4K | Limiter (1440p) |
|---|---|---|---|---|
| Fortnite (Performance mode) | 344 | 344 | 295 | CPU |
| Valorant | 492 | 492 | 492 | CPU |
| Counter-Strike 2 | 410 | 410 | 287 | CPU |
| Apex Legends | 262 | 262 | 164 | game cap |
| Call of Duty: Warzone | 213 | 207 | 107 | GPU |
| Marvel Rivals | 205 | 144 | 74 | GPU |
| Rainbow Six Siege | 451 | 451 | 312 | CPU |
| Minecraft (Java) | 574 | 574 | 574 | CPU |
| Roblox | 240 | 240 | 240 | game cap |
| GTA V | 230 | 230 | 139 | CPU |
| Rust | 180 | 159 | 82 | GPU |
| Cyberpunk 2077 | 197 | 144 | 74 | GPU |
| Helldivers 2 | 189 | 144 | 74 | GPU |
| Elden Ring | 60 | 60 | 60 | game cap |
This pair reaches 144 fps at 1080p in 13 of 14 games and 60 fps at 4K in 14 of 14. Competitive titles use their usual reduced settings; capped games show their cap.
Which part to upgrade first
At 1440p this pair is balanced, so either upgrade helps about equally: no cheaper processor adds much, and no cheaper card adds much. Upgrade whichever part is older, or the graphics card if you plan to raise resolution.
The general rule by resolution is in upgrade CPU or GPU first.
Cheaper or better alternatives
Pairings at a similar total price ($1,200+ class for the pair) that are as balanced or better at 1440p.
Settings that reduce this bottleneck
Because the RTX 4090 is the limiter, every heavy graphics setting buys frames: drop ray tracing first, then shadows, volumetric effects and ambient occlusion, and use DLSS/FSR quality mode before touching texture quality. The processor has 10% headroom, so none of this will shift the limit to the CPU until you are well above the current frame rate. See how to fix a GPU bottleneck.
Core i9-13900K + RTX 4090 FAQ
Is the Core i9-13900K good enough for the RTX 4090 at 1440p?
At 1440p the Core i9-13900K and RTX 4090 are evenly matched: neither part is waiting on the other for long, and you get about 191 fps in a typical modern AAA game.
What FPS will the Core i9-13900K and RTX 4090 get in Elden Ring?
About 60 fps at 1080p, 60 fps at 1440p and 60 fps at 4K at the settings on the methodology page, limited by the game cap at 1440p. It is the most demanding title in our set, so it is the floor for this pair.
Would a faster processor help the RTX 4090?
No listed processor adds a meaningful amount of frames at 1440p; the RTX 4090 is the part to change.
Is the RTX 4090 overkill for the Core i9-13900K?
At 1080p, yes: the Core i9-13900K leaves 33% of the card unused. At 1440p and 4K the card is used far better, so the pairing makes sense if you play at higher resolutions or plan to upgrade the processor later.
More pairings
Both parts have their own pages: Core i9-13900K bottleneck calculator (all GPUs) and RTX 4090 bottleneck calculator (all CPUs).
Not your exact build?
Change the RAM kit, game or refresh rate above, or start fresh in the calculator.