Hello Romas,
thank you for reporting this.
Please be aware that using the noise level limit has much more sense in animation, when you want to make sure each frame has the same noise level.
In your case, I would suggest to run a render for a few passes (10-15), check which part of the picture is the noisiest. Then, using region on that part of the image, check how many passes it needs to get a completely clean render and after that, run a "full" render (means with no regions) with the same number of passes.
You can also check the information about noise and render limits on our help center page:
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https://support.chaos.com/hc/en-us/articles/4528311058961-What-is-noise-level-limit-3ds-Max--
https://support.chaos.com/hc/en-us/articles/4528499329041