PC Bottlenecks Explained: CPU vs. GPU

The Core Conflict

At the heart of every gaming PC is a constant, high-speed conversation between your CPU and your GPU. The CPU is the "brain" that processes game logic, physics, and sends rendering commands. The GPU is the "artist" that takes those commands and draws the beautiful images you see on screen. A bottleneck occurs when one of these components works significantly faster than the other, leaving one waiting and wasting its potential.

What is a GPU Bottleneck?

This is the most common scenario for gamers, especially at higher resolutions like 1440p and 4K. A GPU bottleneck means your CPU is ready to push out more frames, but the GPU can't keep up with the demand of rendering them. You'll often see your GPU usage at 99-100% while your CPU usage is much lower. While it sounds bad, this is often the *ideal* scenario, as it means you're getting the absolute maximum performance from your most expensive gaming component.

What is a CPU Bottleneck?

A CPU bottleneck happens when the roles are reversed. Your GPU is powerful and has rendering headroom to spare, but it's sitting idle, waiting for the CPU to send it the next set of instructions. This is common in fast-paced competitive games running at lower resolutions (like 1080p), where frame rates can be extremely high. In this case, upgrading your CPU would lead to a significant performance uplift.