First: I know that this might also be my PSU (or a fan) but hard drive was my best bet. I posted here 'cause there was no place (I think) where I could've posted about both PSU, and hard drives... A/W let us continue.
So... Recently I have been having this problem. Every time I boot up my computer, Theres a LOUD buzzing noise from the PC. When the computer is turned on, the pitch is low. However, when the boot up process continues, the pitch increases slowly, up to the point where we reach the windows welcome screen. Then the pitch gets lower, and the sound vanishes.
1: I have backed up the small amount of important files I have a while ago, before this problem.
2: It is important that this computer stay alive.
3: What do you think is the problem?
4: It is possible for me to record the sound if anyone needs it.
5: I have tried google, but got mixed results.
6: The sound is... like only one note basically... The broken hard drive sounds I have heard have multiple tones on top of each other + clacking and clicking. (Experience with laptop hard drives)