The fan's running at a fixed speed just under 2000RPM. With or without the LNA made no difference to noise that I could detect. The Seasonic PSU fan is just about audible, perhaps just enough to hide the Noctua fan noise.
I'll block off the side vents later and see what happens.
I ran the system for a day with the side vents covered, made no difference to the HDD temperature.
Good and not surprising. The exhaust fan is effectively drawing the heat out through the rear, as it should.
Indicating the vents add nothing except perhaps ways for noise to leak out........but not likely a factor at all for you since you've got a quiet fan in there. Good job.
I experienced the same uselessness of vents as you did......decided they were mostly a marketing idea as opposed to useful function.
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