Each line represents an estimated FPS ceiling for one component, rather than live usage alone.
To estimate the CPU ceiling, we pair the Core i7-3770K with GeForce RTX 5090, our current GPU anchor. To estimate the GPU ceiling, we pair the GeForce RTX 5090 with Ryzen 9 9950X3D, our current CPU anchor.
The lower line indicates the current limiter, since that component reaches its FPS ceiling first. In most scenarios, that is also the part most likely to deliver the bigger performance uplift if upgraded first.
The percentage shown represents the gap between the two ceilings. In practical terms, it shows how much of the stronger component's potential is left unused because the weaker one becomes the bottleneck first.