At 1440p, the Ryzen 5 7600X or the Core i5-13400 keeps the RTX 4090 from waiting, and a faster processor gains little there. For 1080p and high frame rates, the Ryzen 7 9800X3D, or anything faster.
Which current processors keep the NVIDIA GeForce RTX 4090 from waiting, in a typical game at high settings. Faster than a group needs gains nothing you can see at that resolution, so the useful choice is the least powerful processor in the group you play at. Listed fastest first; each links to the full result for the pair.
None of the older processors in the list keeps up with the RTX 4090 at 1440p: moving to this card from one of them means a new processor too. Check your own pair in the calculator.
Each processor and the RTX 4090 are compared at each resolution with the same model and the same reference data as the bottleneck calculator, which the Bottleneck app uses to judge the hardware it measures. It is an estimate for a typical game at high settings: strategy, simulation and large multiplayer games lean on the processor more, and so do lower settings and upscaling.
An RTX 4090 with the right processor can still fall short of these figures. Bottleneck checks the usual reasons a PC falls short of its parts, free: memory below its rated speed or in single channel, Resizable BAR and GPU scheduling left off, a monitor held at 60 Hz, heat. Then, while you play, it records which part set the pace in every frame.
The free version has no time limit and needs no account. Pro, $9 once, explains each problem and how to fix it, makes the common fixes in one click, and costs out the upgrade for your own PC. Compare the versions