Loud Humming HDD + 100% Disk Usage

[DulestDagger]

So the other day I checked to see if my MoBo needed a BIOS update, it did, so I closed the necessary applications and proceeded with the update. This caused my computer to restart, as soon as the computer came back on the main disk (Toshiba 500GB) began to spin very loudly. It doesn't sound out of the ordinary, but it is a very loud humming noise. Now whenever I power on my computer, the disk spins up loudly the INSTANT I press the power button, even before anything displays on the monitor.

I checked the performance in Task Manager and it is definitely my C: drive (bootable drive) because that one is at 100% as soon as the desktop comes up. I've also checked out the disk health using Crystal Disk Info and SeaTools and the SMART health and all other tests appear to be good. I also reset my BIOS to the optimized defaults (After a bad cmos checksum error), but its odd that it just started doing this after I updated my bios. Additionally, there doesn't seem to be any performance issues or lag when I'm just using the system normally (browsing, running light programs, etc.), however the drive is very loud and annoying. Any ideas what might be the disk to spin so loudly?

Specs:
Windows 8.1
8GB RAM
Disk 1: Toshiba 500GB (bootable)
Disk 2: Seagate Barracuda 1TB
Radeon HD7750
AMD FX 8100
MSI 760GM-P34FX MoBo

 

[hang-the-9]

Install that disk as a seconadry in another computer, see if it's as loud there. There may be something with the firmware of the disk and how the motherboard talks to it after the BIOS update. As a rule of thumb with BIOS, do not update it unless you have an issue you are trying to fix. Or you may end up with an issue you need to fix

 

[DulestDagger]

Alright, got it all fixed, turns out that it wasn't the HDD at all, after I opened up the case and visually inspected what was causing the problem (which I should have done right away), it was actually the CPU fan all along, I simply had to go into my BIOS settings and change the operating fan speed settings (which were WAAAAY too high by default) and voila, much better, thanks for the response and info hang-the-9, I'll keep that in mind in the future.