HDD problems after cleaning PC and updating BIOS.

[Jeremy Zimmermann]

So I decided to clean my self built pc on a day early home from school. It's already running for 2 years now without problems. I tied some loose cables together, replaced a cover on my case's front panel, cleared some dust and finally (I think this is where the problem lies) updated my bios.
Now when I try to boot my pc my HDD LED just doesn't light up, and my HDD is really really slow, and stays stuck at 100%.
I already checked the wiring on the inside if I haven't unplugged a cable, and it was fine.

My PC's (relevant) specs:
Mainboard: ASUS B87M-PLUS
CPU: i5 4670K
HDD: Seagate Barracuda 2TB 7200RPM

And no I do not have an SSD.
Thanks in advance!

 

[ahnilated]

I would unplug the HDD cables and plug them back in first off from both the MB and the HDD's.

 

[Jeremy Zimmermann]

I would unplug the HDD cables and plug them back in first off from both the MB and the HDD's.

Tried it and didn't solve anything

 

[Onus]

After you updated your BIOS, did you check your hard drive settings? For example, if they were set to "IDE" before, but are now set to "AHCI," you'll need to set it back to IDE, then use Google to find the steps for switching from IDE to AHCI that causes the additional required drivers to be loaded.