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OWC Updates Hard Drive DIY Kit For Expanding Factory Installed Storage Capacity for All 2011 iMac and 27″ 2012-Current iMac Models

owcdiyimachdd11_heroOther World Computing today introduced the OWC Hard Drive Do-It-Yourself (DIY) Kit for all 2011 iMac and 27″ 2012 iMac models. The kit enables iMac owners to replace the factory installed internal hard drive with up to a 6.0TB hard drive for expanded storage and backup capacity. Fully supported with step-by-step video and installation tools, the kits feature a custom power cable with an in-line digital thermal sensor that ensures proper factory fan operation and full compliance with the Apple diagnostic testing.

The Problem: Custom Drive Firmware

With the introduction of the 2011 iMac, Apple factory drives contained custom firmware that communicates thermal data to the System Management Controller (SMC). Standard, retail replacement drives do not contain that firmware, and Apple does not make it available to third-party manufacturers. Without proper communication, the SMC is unable to monitor hard drive temperature to regulate iMac fan speed. As a failsafe, the blower fans run at full speed and the Apple Hardware Test will report a failure. Despite various ‘hacks’ and workarounds (one that simply disables SMC monitoring, which can potentially lead to hard drive or system damage) the best solution had been to skip the upgrade and settle for Apple’s factory drive. For more information on this topic, visit the OWC Blog.

The Proven Solution: OWC Hard Drive DIY Kit w/Thermal sensor module

The OWC Hard Drive DIY Kit provides a custom engineered digital module with a thermal sensor which installs in-line between the new drive of the customer’s choice and the existing Apple factory cabling. The thermal module is programmed to communicate drive temperature data to the SMC in a similar manner as the original, factory installed drive. Now all 2011 iMac 21.5″ and 27″ owners, and all 27″ 2012 iMac owners can:

  • Install any standard 3.5″ Serial ATA hard drive with capacities up to 6.0TB
  • Retain proper cooling via SMC bay monitoring and fan speed management of the hard drive bay per Apple factory settings
  • Pass Apple diagnostic testing

“The Hard Drive DIY Kits for 2011 and later iMac models represent OWC’s steadfast commitment to the DIY upgrader/servicer,” said Larry O’Connor, Founder and CEO, Other World Computing. “Our kits represent the only complete, proven solution for obtaining higher storage/backup capacity while retaining proper system operation.” 

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  • Now, I installed a Samsung 840 EVO ssd with this thermal sensor connector. I started up the iMac and the fan ramped up to full speed. What is wrong?

    • I’m sorry to hear that. There are a few steps that can be taken to troubleshoot this, so it would be best to contact our tech support team via phone at 800-869-9152, or 815-338-8685 internationally; by chat; or by e-mail for the best service.

  • Hi,

    I’ve set up the thermal sensor some time ago. I wanted to change my HDD with bigger capacity but the adhesive on the small part of the thermal sensor doesn’t stick anymore. I don’t want to do wrong thing.
    What do you recommend to fix that -without buying a new themral sensor ;-)?

    Thanks a lot

  • Have you a solution for the hard drive temperature sensor on the late 2009 27″ iMac? What about SSD drives replacement with temperature sensor, or is that not a problem with SSD drive?
    Can I send you my iMac to replace drive for me, and what is involved with that procedure as far as cost?

    • Our recommendation for 2009 iMacs is to buy an identical brand drive. We have a separate blog post for the 2009 and 2010 models.

      We do offer custom installation services. Please contact our sales team for more information.

  • Anything on a DIY hard drive replacement for a late 2009 27″ iMac? I just had a hard drive failure!

    • Our recommendation for 2009 iMacs is to buy an identical brand drive. We have a separate blog post for the 2009 and 2010 models.

  • I wish, I wish, I wish… that OWC create a PCIe solid state drive upgrade for the Retina 15″ Macbook Pro late 2013. Please make it 2 TB.

  • I’m not sure if this is the right blog for my question, but here it is:

    I added solid state drive to my mid 2010 27″ iMac and made it a Fusion Drive as per OWC instructionsd its working OK. But I wanted to install an Antivirus and there is some remnants in the system that that software doesn’t like and won’t install. I want to erase all the programs and reinstall them and the System. If I erase everything will I have to re-format in order to have the Fusion part or can I just delete everything and reinstall from another HD that has all the parts (including the antivirus) working?

    • If you followed the steps in our blog for creating a fusion drive then erasing the drive within Disk Utility will not break the fusion drive. The Fusion drive setup is a lower level of formatting then what the Disk Utility application has access too.

      Any further questions on your Fusion drive, We’d recommend posting to the previously linked Fusion drive blog.

  • I am glad that owc is still selling a solution for the 2011 imac. I am still on the fence of doing the turnkey 2011 solution vs a thunderbolt external ssd boot drive.