CPU–GPU Bottleneck

• It is workload-dependent: the same PC can be CPU-limited in one game and GPU-limited in another.
• Lower resolutions shift load toward the CPU; higher resolutions shift it toward the GPU.
• Frame caps, V-Sync, power-saving modes and slow memory can mimic a bottleneck.
• Diagnosis relies on observing GPU utilization and per-core CPU load during real gameplay.

Each frame is prepared by the CPU (game logic, draw calls) and rendered by the GPU. Throughput is set by the slower stage.

Raising resolution increases GPU work per frame while CPU work per frame stays roughly similar, which is why CPU limits are most visible at lower resolutions and high refresh rates.

Graphics cards connect through PCI Express, which is backward compatible across generations; the standard is maintained by PCI-SIG.