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1 Hard drive clicking even after switching drives
I was just surfing the web when my hard drive started to click. It sounded really bad so I turned it off. I was able to boot into safe mode without it clicking. It sounded fine and I ran first aid on the drive and nothing was wrong. I was still skeptical that my hard drive was about to fail so I replaced it and tried again to boot it up and it continued to make a clicking noise so I shut it off. I have no idea what what the problem is since when I switched the hard drive it was the same noise.
Update (06/01/2016)
I replaced the optical drive with a hard drive a while ago so I able to still boot the computer just not in the main hard drive slot. Any other hard drive I tried there made the clicking sounds and so I replaced it with a dead SSD so that my computer would boot and there wouldn't be horrendous noises.
Is this a good question?
971 
2 Comments
Do you have an external HD case or a SATA to USB adapter? I would give that a try to see if the original drive still works (externally). Do you have a bootable drive or OS install CD/DVD?
by Dan
When was the last time you ran Antivirus software on your Apple? Even apples do get viruses from time to time. And many viruses target the HDD. Also your HDD Controller Hardware might be going bad on the Main board. But I would do a AV Scan first just in case.
by Brian Reeder