|FYI, that's the CD Drive. Your hard drive is something else. :)|
If I were you, I'd start troubleshooting with unplugging the CD Drive. Remove the side panel of your computer, and with the PC unplugged, locate the back of your CD drive. On the back towards the right of the drive is a power cable. Unplug it. Then reconnect the power and boot back up. If that doesn't work, we'll try something else.
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