You just got a spanking new laptop with loads of RAM, the latest processor and very high performing Graphics card.
You download one of the most graphic-intensive games Far Cry 5 and open the game to play it. You keep all the graphic settings to Maximum with Textures, V-Sync, G-Sync, and other options turned ON for the highest quality gameplay.
You start the game and keep on playing it with a good frame rate or FPS of more than 60. Everything seems okay until you see something horrible.
The frame rates or the FPS suddenly drops below 30 and you observe stuttering and lags. The FPS stays below 30 for some time and then it again rises back to 60 and above.
The process keeps on repeating. You go from very high FPS to very low FPS in a matter of minutes. This is happening even though you’ve got a laptop with great specs that are good enough to run the game at an FPS of over 60 continuously.
Well, this phenomenon of the continuous rise and fall in the FPS is due to a process called CPU/GPU Bottleneck.
What Does Bottleneck Mean?
A CPU Bottleneck is a process in which the CPU cannot keep up with the processing speed of GPU. This causes a huge drop in the FPS.
Your CPU will be at maximum usage(100% usage) but the GPU usage will be very less. This occurs if you use an old fashioned CPU with a newer GPU model.
This drop in FPS causes lags and stuttering leading to a poor gaming experience.
A great example of Bottleneck is Traffic moving from a very large and wide road to a small and narrow road.
When the traffic is moving on a large road then a lot of cars can move together but when the traffic moves on a narrow road then only a limited number of cars can move together.
This narrow road creates a Limit to the number of cars that can move thereby causing a Bottleneck.
Let me give you an example of how Bottleneck occurs in a computer.
If you use a custom-built desktop PC with a 6th Generation Intel Core i3 processor with an NVIDIA GeForce RTX 2080 Ti Graphics Card then you will observe CPU Bottleneck.
This is because your CPU is very old compared to the GPU and the CPU doesn’t have enough processing power to keep up with the high processing power of the RTX 2080 Ti GPU.
The video above shows the perfect example of CPU Bottleneck while playing a game. The game stutters and lags when the CPU Performance is 100% and the GPU usage is very less.
The continuous rise and fall in FPS is because the GPU has to wait for the CPU to process the previously sent data before the GPU can send some more data to the CPU to process.
The CPU usage remains at 100% for the entire period while the GPU usage rises when it sends the data and falls when it has to wait for the CPU to process the data.
What Is A GPU Bottleneck?
A GPU Bottleneck is the process in which the GPU cannot keep up with the processing speed of CPU. This is the exact opposite of CPU Bottleneck.
Your GPU will be at maximum usage(100% usage) but the CPU usage will be very less. This happens if you use an old model of GPU with a newer CPU model.
For example, if you use a custom-built Desktop PC with a 10th Generation Intel Core i9 Processor with NVIDIA GTX 480 Graphics Card. Here, the processing power of the GPU is very less compared to the processing power of the CPU.
The GTX 480 cannot keep up with the high processing speed of the Intel Core i9 processor and this causes a GPU Bottleneck.
Other Causes Of CPU/GPU Bottleneck
The outdated CPU and GPU models is not the only cause of CPU/GPU Bottleneck. It can also happen with the Type of Game you’re playing.
There are basically two types of game mainly CPU Dependent Games and GPU Dependent Games.
CPU Dependent Games show high framerates or FPS under Low Graphics Settings. An example of such a game is Civilization 6 or Resident Evil 7.
GPU Dependent Games show low framerates or FPS under Low Graphics Settings if the GPU doesn’t have enough processing power. Example – Far Cry 5, GTA V, etc.
You can increase the framerates or FPS of these games by using a powerful GPU with high processing power.
How To Reduce CPU/GPU Bottleneck
If you’re observing CPU/GPU Bottleneck in Laptops then you cannot fix it completely. You can, however, reduce the Bottleneck effect by the following methods.
(A) You can reduce CPU Bottleneck in Laptop by overclocking the CPU and undervolting and underclocking the GPU.
(B) You can reduce GPU Bottleneck in Laptop by overclocking the GPU and undervolting and underclocking the CPU.
Following the above two methods can reduce the Bottleneck effect somewhat but it cannot remove it completely.
How To Fix CPU/GPU Bottleneck
If you’re using a desktop PC then you can fix the CPU/GPU Bottleneck by replacing the component that is causing this Bottleneck.
You can fix CPU Bottleneck by replacing the old CPU with a new and better quality CPU.
You can fix GPU Bottleneck by replacing the old GPU with a new and better GPU.
Is CPU/GPU Bottleneck Bad
CPU/GPU Bottleneck is bad for Gaming but it won’t harm your computer. This won’t cause any serious damage to your computer unlike CPU Throttling or GPU Throttling.
You will only notice low FPS in Games with Lags and Stutters but it won’t affect your daily tasks like Browsing the Internet, Watching Movie and other tasks.
Even though it is safe it doesn’t mean you should use a laptop or desktop with CPU/GPU bottleneck. If you specifically bought the computer for gaming then you won’t get a good gaming performance which doesn’t satisfy your main purpose.
You can reduce or fix the CPU/GPU Bottleneck problem by following the methods shared above.