Question CPU Clock Speed Limit and Bottleneck


Feb 17, 2021
My CPU is i5-10400 and my GPU is RX 570. According to Bottleneck Calculator, it has 10.76% GPU bottleneck because the GPU is too weak. In windows 10, there is an option to limit CPU clock speed. If I limit the CPU clock speed to 85%, it has no bottleneck. Is it safe and won't it harm my CPU if I do this? Thank you!
There is no such thing as "bottlenecking"
If, by that, you mean that upgrading a cpu or graphics card can
somehow lower your performance or FPS.
A better term might be limiting factor.
That is where adding more cpu or gpu becomes increasingly
less effective.

How is your setup performing?
If it needs to get better, find out what YOUR limiting factor is.

My stock approach to this perennial question:

Some games are graphics limited like fast action shooters.
Others are cpu core speed limited like strategy, sims, and mmo.
Multiplayer tends to like many threads.

You need to find out which.
To help clarify your CPU/GPU options, run these two tests:

a) Run YOUR games, but lower your resolution and eye candy.
This makes the graphics card loaf a bit.
If your FPS increases, it indicates that your cpu is strong enough to drive a better graphics configuration.
If your FPS stays the same, you are likely more cpu limited.

b) Limit your cpu, either by reducing the OC, or, in windows power management, limit the maximum cpu% to something like 70%.
Go to control panel/power options/change plan settings/change advanced power settings/processor power management/maximum processor state/
This will simulate what a lack of cpu power will do.
Conversely what a 30% improvement in core speed might do.

You should also experiment with removing one or more cores/threads. You can do this in the windows msconfig boot advanced options option.
You will need to reboot for the change to take effect. Set the number of threads to less than you have.
This will tell you how sensitive your games are to the benefits of many threads.
If you see little difference, your game does not need all the threads you have.

It is possible that both tests are positive, indicating that you have a well balanced system,
and both cpu and gpu need to be upgraded to get better gaming FPS.


May 26, 2020
Gpu bottleneck is not a problem, cpu bottleneck is bad depending on how bad or old the cpu is, for example if your cpu is too old and the gpu is the best one in the market, then what will happen is the gpu will be so fast, that it will start churning up frames so fast that the cpu can't keep up, which will translate to lag or choppy visuals.

Whereas in case of gpu bottleneck it's not a problem. Unless there is massive miss match even that is manageable.

So in your case you don't need to underclock your cpu
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