This is shown on the video, simply disable nVidia reflex in options as it's causing very high CPU usage, in KF3 it doesn't really make it any smoother, it just hogs CPU for no reason. aiming / mouse movement is smooth enough when it's disabled.

This is also shown on video, if you're having issues with high GPU usage, then these settings can eat a lot of GPU:

1. global illumination method - turn this from lumen to off

2. reflection method - lumen eats lot GPU, SSR eats less, but still a lot. turn it off for best performance.

3. turn shadows to low, it's shown on my video, that difference between low and ultra, is VERY minimal and barely noticeable, you will only notice if you have side-by-side screenshots, one with low and one with ultra, but GPU usage can go up a good 10-30% depending on your GPU

4. turn off any recording software when not needed, i noticed my GPU goes from about 105 watts of power to like 210 watts of power when recording. this includes steam recording or some windows game recording thing, any recording software WILL use more GPU.

5. turn normal reflections to low or medium.

6. turn view distance to low.

Those options will significantly improve performance and lower GPU usage, with minimal visual impact. personally i don't like raytracing (lumen), it makes everything look too dark and KF3 is already DARK game as it is, so having lumen off is much better in my eyes.

If you want to know what each thing does, then take a screenshot, don't move your character/mouse, change the setting you are testing, then take another screenshot, open the photos and compare side by side or just flick between them back and forth to see differences (like how i did on the video).