My Ubuntu always uses more CPU than Windows 10 pro for doing anything, but it's always dismissable as it's just a spike. Until I used these two applications.

Using OBS to display recorded video(VLC video source) constantly uses about 60% of my CPU alone. My setting for the video output:
_ 1280x720 display
_ Bicubic filter
_ 10 fps value
_ NVENCE encoder

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Using Chrome to join google meetings with the camera on would use about 50% in general, with or without OBS virtual camera.

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Compare to Windows 10 pro which consumes less than 15% of my CPU in every circumstance(The GPU is just a spike, would die down after a second or two). They both have the same setting when it comes to resolution and such for google meetings. enter image description here

My spec:
_ Core i7 gen 10th
_ Nvidia RTX 2060
_ 512 SSD
_ 16GB Ram
_ Nvidia driver 470, I have Nvidia performance mode on in general.
I have secure boots turn off, along with fast startup, and Ubuntu is installed with EFI format. I am using a Dell G5 5500 laptop. Is there any way to reduce or fix this? Please help me.

  • Do these CPU percentages represent the same in Linux and Windows? For Linux, the percentage shown is a percentage of one core, as program probably runs on one core only. Press "1" in top and you will see how other cores are occupied. For Windows, I believe the CPU usage of the process displayed is a percentage of your total available CPU resources. At least that is what I found on internet, as I do not know Windows that much.
    – nobody
    Sep 27, 2021 at 6:48

1 Answer 1


In Linux 100% CPU use is when a single CPU core is fully loaded, while in Windows 100% CPU use is when all CPU cores are fully loaded.

Since you have a Core i7 CPU you must have at the very least four CPU cores and 8 logical threads which translates Windows 2.8% into roughly 22.5% Linux CPU use which is not too far away from what Linux actually shows to you.

Another very important thing to consider is CPU power savings.

Imagine your CPU is running at its full speed, e.g. 5GHz, then a task consuming 1GHz will be shown as 20% under Linux or 1/8 of that under Windows.

However if under Linux your CPU is running at e.g. 2GHz instead, then its CPU use will be 50%.

Lastly, Windows at its current state provides better (read faster and more optimized) APIs for hardware video encoding and decoding as well as GUI rendering, so normally Windows will be more power efficient.


  • Linux and Windows show CPU use differently
  • You must take CPU frequency into consideration because it's the basis of calculating CPU use both under Windows and Linux
  • Okay thank you, can you tell me if there is any program that allows you to watch the total usage rather than the individual core of a CPU? Sep 27, 2021 at 11:51
  • top and htop show everything you need. Sep 27, 2021 at 11:59

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