CPU And GPU Bottleneck Detailed And Easy Explanation

June 20, 2025June 21, 2025 TNHindi Tech Gamer CPU And GPU Bottleneck, CPU And GPU Bottleneck Detailed And Easy Explanation

CPU And GPU Bottleneck

If you’re into PC gaming, I’m pretty sure you’ve heard the terms CPU and GPU bottleneck. And obviously, if you are into PC gaming and have to know about CPU and GPU bottleneck. Now, you’re here because you do not fully understand what the CPU and GPU bottleneck is. And want to learn what exactly it is? Why does it happen, and what is wrong with it? How to identify if you’re experiencing it? And how to fix the bottlenecking issue?

Well, that is what I’m going to be covering in detail. So let’s get to it. Before talking about CPU and GPU bottleneck, let’s first understand what bottlenecking is.

CPU And GPU Bottleneck: What Is Bottlenecking? And Where Does The Term Is Come From?

In simple words, the bottleneck is just the neck of a bottle. When you’re pouring a liquid out of a bottle and a glass, you’ll notice the glass water came out more quickly as compared to the bottle. That is happening because the narrow neck of that bottle restricting the flow and limits the amount of water to go out. On the other hand, the glass mouth completely open, and there is nothing that can restrict the water flow.

But, what does that have to do with CPUs and GPUs? Well, the CPU and GPU work together to run games. CPU takes the data, processes it, and feeds it to GPU. If there is a huge difference in input and output data, the bottleneck will likely happen.

CPU Bottleneck

Now switch over to our gaming PC. Instead of water, of course, what we want is as many frames per second flowing from our graphics card as possible. We don’t want to have anything that restricting our graphics card from it being able to do its job to its absolute potential. Now to run the GPU at its full potential, we need the CPU to be fast enough that can process and deliver the data such as keyboard input, mouse input, game actions, game assets, game physics, UI, audio, etc to the graphics card.

The faster the CPU processing the data and send it to GPU, the faster the GPU does its job and resulting in more frames. Ideally, you want your CPU to feed raw commands to your GPU as fast as your GPU can produce new frames. You want to have your GPU utilization at 100%. That means the GPU is working as fast as it can and outputting the maximum number of frames.

If your CPU isn’t powerful enough to processing data and send that data to the GPU on time, the GPU ends up sitting idle for fractions of a second. Means your GPU will output fewer frames per second even though it’s capable of more fps. This is called a CPU bottleneck because your CPU is restricting or slowing down your GPUs performance.

Example Of A CPU Bottleneck

A perfect example would be if you pair GTX1660 with AMD A10 5800K.

In this benchmarking footage from Shadow of the Tomb Raider at 1080p, a GTX 1660 paired with an AMD A10 5800K, which is a pretty old and pretty underpowered CPU by today’s standard.

As you can see here, the CPU utilization is at 100% but, the GPU utilization is between 50% and 70%. The CPU is running at its maximum performance. But, it is unable to send raw commands to the GPU fast enough. This results in the frame rate being in the 30fps-40fps.

Now, pair the GTX1660 with a Ryzen7 2700X with the same graphical settings.

We see the GPU utilization pretty well max out at 98%. And the CPU utilization stayed much lower than before at around 20-30%, giving us a consistent 60 plus frames per second.

GPU Bottleneck

So what about a GPU bottleneck? Well, it’s the same concept as CPU but another way. Meaning the CPU is fast enough to process data and feed to GPU. But the GPU itself is not fast enough to handle the incoming data to process.

Well, unlike a CPU bottleneck, a GPU bottleneck isn’t necessarily a bad thing. When it comes to gaming, it is what you want to have. A GPU bottleneck occurs when your GPU is running at 100% utilization, but your CPU is not.

Just like the above benchmark, the GPU is running at 100%. But the CPU is far from that. In this scenario, the CPU is processing the game really fast. But the GPU can not handle that amount of data to process quickly. Sometimes it is good. Because it means my GPU isn’t being slowed down. But, it also means the graphics card can be upgradable without worrying about CPU bottlenecking.

Causes Of CPU And GPU Bottleneck

So why CPU and GPU bottleneck happens? As I said earlier, either a slow CPU or slow GPU could be the main reason. But that is not always the case. CPU and GPU bottleneck can depend on games to games. There are such games that mostly either CPU or GPU-dependent.

Games that usually have a high frame rate even though the GPU the low-end are considered CPU-dependent games. Such as Minecraft, AC: Black Flag, etc. On the other hand, the games which frame rates differ with the different graphics card usually fall under the GPU-dependent category. These are also the games that demand a better graphics card for a decent performance. Also, these games have better and realistic graphics.

How To Identify CPU And GPU Bottleneck?

To identify whether the CPU is bottlenecking or the GPU, you can use utility software like MSI Afterburner and Riva Tuner(Riva Tuner comes with the afterburner, so you don’t need to install both separately) to monitor the usage of different components of your PC.

Here Are The Steps To Monitor Hardware Usage And Game Frame Rate.

Step1:

Download the MSI afterburner. Install and open it. When you start Afterburner, Riva Tuner starts automatically.

Step2:

First, on the Rive Tuner window, turn on the Show On-Screen Display.

You can also turn on start with Windows, so you don’t have to do this every single time when starting your PC.

You can play with other options to customize it if you wish.

Step3:

On the MSI Afterburner window click on the settings icon.

Step4:

Click on the Monitoring tab.

Step5:

Under the “Active hardware monitoring graphs“, you can see the list that you can monitor while playing games. Such as GPU and CPU temps, GPU usage, CPU Usage, etc.

Just click the left side of the list item to enable the monitoring.

Step6:

Click on Show in On-Screen Display under GPU temperature graph properties.

Step7:

Click Apply and hit OK.

Eliminate CPU And GPU Bottleneck.

If you are experiencing a CPU bottleneck, unfortunately, there’s not really anything you can do to fix it outside of upgrading to a more powerful CPU.

Although you can apply these options to increase CPU performance as much as you can.

Increase the in-game graphics setting so the GPU will take time to render the game.
Stop unnecessary software that uses CPU in the background.
Overclock the CPU. Overclocking CPU can increase a little bit of performance.
Overclock the RAM. Overclocking the RAM can give a boost in performance.

On the flip side, if you’re experiencing a GPU bottleneck, overclocking GPU can increase its performance a little bit. Or decreasing the in-game graphics settings.

If your GPU is bottlenecking, you have the option to upgrade your graphics card without even needing to upgrade the CPU.

Excellent question — let’s break down CPU and GPU bottlenecking in a clear, simple, and detailed way. I’ll explain it like a story you can easily picture, along with how to check and fix it too.

📌 What is a Bottleneck (in PC terms)?

A bottleneck happens when one part of your computer (either the CPU or GPU) is much slower than the other — limiting overall performance because it can’t keep up.

Imagine you’re filling water into a bottle:

No matter how fast you pour, the narrow bottleneck (the bottle’s neck) controls how much water passes through.
Same for a PC: even if one part is super fast, the slow part limits your game’s performance.

📊 How CPU and GPU Work Together

When you play a game:

CPU: Handles calculations, AI, physics, player input, background processes.
GPU: Draws images, graphics, lighting, 3D models, textures.

They work like a team. If one is too slow, it drags the other down.

🖥️ What is a CPU Bottleneck?

It happens when:

The CPU is too slow to send enough instructions to the GPU.
So your powerful GPU is underused, sitting idle waiting for the CPU.

🔍 Example:

You have an RTX 4060 (powerful GPU) but an old i3 CPU.
Even though your GPU can handle 120 FPS, your CPU can only manage 60.
Result: Game runs at 60 FPS. The GPU is wasting potential.

Signs of CPU Bottleneck:

High CPU usage (90–100%), while GPU is low (40–60%).
Choppy performance in open-world or physics-heavy games.
Stuttering in games with many NPCs or AI enemies.

🖥️ What is a GPU Bottleneck?

It happens when:

The GPU is too slow to render the graphics the CPU is sending.
The CPU finishes its work, but the GPU is overloaded and can’t keep up.

🔍 Example:

You have a Ryzen 7 5700X (powerful CPU) with an old GTX 1050 Ti.
CPU could run the game at 144 FPS, but the GPU can only handle 40.
Result: Game runs at 40 FPS because GPU is maxed out.

Signs of GPU Bottleneck:

High GPU usage (90–100%), while CPU is low (30–50%).
Low frame rates even if CPU is not fully utilized.
Smooth physics, AI, menus — but poor graphical performance.

🎮 Does Bottlenecking Always Matter?

A little bottleneck is normal — 10–20% imbalance is fine.
Big gaps (like 100% CPU and 50% GPU) waste system potential.
It affects gaming, video editing, and VR performance the most.

📈 How to Check for Bottlenecks

Use tools like:
- MSI Afterburner (free) — overlays CPU & GPU usage in games.
- HWMonitor — shows temps and usage while gaming.
Watch usage numbers:
- If CPU is 100% and GPU is below 60% → CPU bottleneck.
- If GPU is 100% and CPU is low → GPU bottleneck.

⚙️ How to Fix Bottlenecking

For CPU Bottleneck:

Lower graphics settings like draw distance, physics, AI counts.
Close background apps.
Upgrade to a better CPU.

For GPU Bottleneck:

Lower resolution and texture settings.
Enable DLSS / FSR (if supported).
Upgrade to a better GPU.

Balance matters: A well-matched CPU-GPU combo ensures both parts work around 80–95% load together.

📊 Example Balanced PC Setups:

CPU	GPU
Intel i5-12400F	RTX 4060 / RX 7600
Ryzen 5 5600X	RTX 3060 / RX 6700 XT
Intel i7-12700F	RTX 4070 / RX 7800 XT

✅ Summary (Simple Explanation)

Bottleneck Type	What Happens	How to Spot it
CPU Bottleneck	CPU too slow for GPU	CPU at 100%, GPU low usage
GPU Bottleneck	GPU too slow for CPU	GPU at 100%, CPU low usage

Would you like me to suggest a balanced build for your budget or check your current PC bottleneck potential? I can help with that too — just share your specs! 🚀