2010 27" iMac new HDD and loud fan problems

Evildude683

macrumors regular
Original poster
Aug 8, 2012
134
1
Republic of Texas
I recently decided to add an SSD to my Mid 2010 27" iMac while keeping the original HDD for storage. I purchased part 922-9531 to be able to keep both drives. Needless to say that the installation was a fun experience.

Unfortunately, soon after I put together the machine I noticed that the fan in the lower left corner (CPU) was running really loud and likely at a higher speed. After searching around the web, I proceeded to make sure all my connectors were properly seated, again the result was the same.

I also noticed that my Mac boots just fine from the SSD running Sierra, but is unable to see the original HDD. I went ahead and re-opened mac and switched he power connectors to rule out any failures with it. The results was the same, only the SSD was visible.

Thinking somehow the drive just died on me, I went ahead and purchased a new Seagate Firecuda that would give me the speeds on an SSD with the max storage capacity of the an HDD. Same thing! The iMac never saw it and I was unable to install the OS on it, I also tried plugging it to my gaming rig with the same results. I thought I must have gotten a bad drive so I requested a replacement with Amazon and now the replacement drive is doing the exact same thing.

Either my iMac is somehow killing HDD drives, Amazon has a bad batch of Firecuda in stock or who know what.
It is worth mentioning that ssdfanctrl did not solve the issue for me.

Any advice?
 

Evildude683

macrumors regular
Original poster
Aug 8, 2012
134
1
Republic of Texas
Have you tried Mac Fan Control to manually operate the fan settings. Also, yes on the digital sensor if you want to put that in.
I have installed the OWC thermal sensor according to the instructions and the fan still running loud. I even completely removed the mechanical HDD.

When you switched the SATA power connector did you also switch the SATA data connector?
Yes.

I also ordered a desktop 3.5 HDD docking station and managed to finally initialize the Seagate Firecuda. I'm thinking maybe the new power cable (922-9531) may be the culprit. I may end up putting the original cable in and just using the Firecuda as my main drive if it will silence the fan.
 

retta283

macrumors 6502a
Jun 8, 2018
976
661
Kingman, AZ
I have installed the OWC thermal sensor according to the instructions and the fan still running loud. I even completely removed the mechanical HDD.


Yes.

I also ordered a desktop 3.5 HDD docking station and managed to finally initialize the Seagate Firecuda. I'm thinking maybe the new power cable (922-9531) may be the culprit. I may end up putting the original cable in and just using the Firecuda as my main drive if it will silence the fan.
You'll still want to try MacsFanControl to see what's going on with your HDD and other sensor temps.

I have a 2010 iMac too, and I had the same problem with a new HDD. MacsFanControl shows that some of the sensors are stuck for the HDD (don't remember specifics) and won't change temps. So I need to install a new one.