So this whole thing has been different. It used to be me turning on pc and hearing sorta fan scratching sound, after turning off pc and turning it back on it would fix itself. Then after a couple months something in my pc started buzzing (whole pc vibrates but i feel it the most on the motherboard side) also would fix itself.
Then another year later, I got a new buzz that's very loud with the one that I had before, the loud one goes away after shutting down pc, and turning it back on, but the second one doesn't and stays either for whole day, or couple hours later it just stops.
Another thing: The loudest sound seems to go away as soon as some fan spins through fully and I turn off the pc, not just randomly, I can hear it sort of build-up)
Here's a video of the sound, and it disappearing after turning off pc, and then back on
View: https://www.youtube.com/watch?v=kITsAikBrZU
Then another year later, I got a new buzz that's very loud with the one that I had before, the loud one goes away after shutting down pc, and turning it back on, but the second one doesn't and stays either for whole day, or couple hours later it just stops.
Another thing: The loudest sound seems to go away as soon as some fan spins through fully and I turn off the pc, not just randomly, I can hear it sort of build-up)
Here's a video of the sound, and it disappearing after turning off pc, and then back on