Just tried again and... I don't get it. Did a noise reduction twice and both times I got a buzzer sound but no significant rise in temperatures. First time, it jumped to 42 degrees and later on, 38 degrees. One strange thing ( except the buzzer ) was that max CPU fan speed recored by HW Monitor was 1341 RPM which would be about 100%. Why is it strange? This was the first time my motherboard decided to run the fan much faster than 1000 RPM.
I guess I'll have some "fun" tomorrow trying to figure this out. I doubt I'll find out much, though. I think my only buzzer warning enabled is CPU temp. I'll have to check to make sure if there was anything more than CPU temp and CPU fan warning ( disabled as it went off with fan in "idle mode" ).
Ok, something more. It goes like this:
1. buzzer sound
2. slight temp jump and extreme fan speed jump to 90-100%
3. here's the strange one - fan speed drop to 0 RPM for a fraction of a second
4. fan speed back to normal
Looks like some kind of problem with the fan, it can't really drop to 0 RPM in such a short time but it could lose power for a moment for some reason. Why the buzzer, though?