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We recommend DIY Kit for 2011 27" iMac's internal SSD bay: 480GB OWC Mercury Extreme Pro 6G SSD. (Mfr P/N: K27IM11SP480) from Other World Computing for $139.51 as a suitable alternative.

DIY Bundle

and Internal SSD Kit for 2011 27" iMacs

Mercury Extreme Pro SSD and SSD Bay Solution
Upgrade with Confidence!
The complete solution for your 2011 iMac
Configuration flexibility is yours when you add a second internal drive using the OWC SSD bay kit. Boost your storage capacity by adding additional storage, and enjoy near-instantaneous boot and app loading times thanks the performance of an OWC 6G SSD.
Fast and reliable solid-state storage
With incredible sustained data speeds, up to 100X greater data protection than enterprise class Hard Disk Drives, and RAISE technology for RAID like data protection and reliability, the OWC Mercury 6G SSD line delivers unbeatable performance, that's backed by an incredible OWC SSD Limited Warranty.
We are here to help
OWC's SSD bay kit comes backed by OWC's award-winning U.S.A. based technical support team which is readily available to assist you with your upgrade should you have any questions. If you are not fully confident of your ability to add an SSD to your 2011 27-inch iMac, you can choose to have OWC "Do It For You" via our Turnkey Upgrade Installation Program.

Please note, that before attempting to perform this installation, it is recommended you watch the associated instructional video in its entirety to determine your ability to perform this complex procedure. OWC assumes no responsibility for damage that may occur during the install.

Release Candidate (RC) firmware set

There are two kinds of firmware for SSDs Mass Production (MP) and Release Candidate (RC). Prior to an MP firmware release, there are beta firmware releases and an RC firmware release. Often, the RC is the same as the MP release, however there can be small changes and bug fixes made between the two. OWC has evaluated the RC for the 6Gb/s SandForce 2281 Processor and found it to be stable with no issues reported during our testing. However, as with any evolutionary product, issues may surface as different usages and configurations are employed and it is important to understand that there will be further updates and revisions.

Since no firmware update is currently offered for the OWC Mercury EXTREME Pro 6G SSD, no update page exists. To see the typical steps involved with a self performed field firmware update, please visit our 3Gb/s product update page at: http://eshop.macsales.com/Customized_Pages/Framework.cfm?page=sf_firmware.html

It is important to note that the current firmware update tool requires the use of Windows XP/Vista/7. OWC is currently working on a Mac OS based update tool, but we do not have an exact availability date.

120GB Mercury Extreme Pro 6G SSD Specifications:


SandForce 2281 Series Processor with 7% Over Provisioning
Tier 1 Major Multi-Level Cell (MLC) High-Performance Sync-NAND Flash
Form Factor
Standard 7mm 2.5"
SATA 6Gb/s, 3Gb/s & 1.5Gb/s supported, SATA 3.0 Compliant
120GB useable capacity
Total Flash Memory Components – 128GB
8GB allocated to real-time data redundancy & error correction
Formatted Capacity2
RAID Support
Qualified for single drive and multiple drive production workstation RAID 0/1/10/0+1 and SPAN usage.
SMART Attributes
Native Command Queuing
up to 32 commands
Manufacturer Model Number
RoHS Compliant


Height (max)
7mm (0.276″)
OWC 7mm – 9.5mm Adapter
1 included (buy additional)
Width (max)
70.06mm (2.758″)
Length (max)
100.12mm (3.941″)
77 grams +/- 2 grams
0.170 lbs +/- 2.71 oz


Data Reliability
ECC Recovery: Up to 55 bytes correctable per 512-byte sector
Chip Based Data Encryption: 128-bit AES-compliant
TRIM Support
OS Dependent
Nonrecoverable Read Errors
Less than 1 sector per 1016 bits read


Reads 6Gb/s (up to)
Writes 6Gb/s (up to)
Reads 3Gb/s (up to)
Writes 3Gb/s (up to)
Read Incompressible
Data Rate (up to)
Write Incompressible
Data Rate (up to)
Random 4K Read4
Up to 60,000 IOPS
Random 4K Write4
Up to 60,000 IOPS
Read Latency
less than 0.1ms
Write Latency
less than 0.1ms


Read: 3000mW (3.0W) Maximum draw
Write: 4500mW (4.5W) Maximum draw
Less than 1000mW (1.0W)

Environmental (Operating)

Temperature (°F)
32°F to 158°F
Temperature (°C)
0°C to 70°C

Environmental (Non-Operating)

Temperature (°F)
-40°F to 185°F
Temperature (°C)
-40°C to 85°C


Idle (Typical)
0.0 bels
Seek (Typical)
0.0 bels
  1. 1GB = 1,000,000,000 bytes. Total accessible capacity varies depending upon operating environment (typically 5-10% less). The actual total capacity will depend on your own defined file settings/preferences. 
  2. In terms of standard gigabytes, 1GiB ≈ 1.074GB and refers to the actual formatted capacity of shown under Mac OS 10.5 or earlier and Microsoft Windows OS.
  3. Specific application environments such as temperature and duty cycle will affect the overall reliability.
  4. Specifications provided by SandForce.
  5. Temperature reporting is currently an unsupported feature because due to the operating characteristics of SSDs, it is highly unlikely one would ever exceed an OWC Mercury SSD's stated operating temperature ceiling of 158F/70C. However, we are looking into supporting this feature in the future via a firmware update. Firmware updates can be found here: http://eshop.macsales.com/tech_center/OWC/SSD.

Manufacturer provided specifications for Other World Computing p/n K27IM11SP120 UPC#: 812437025996


SSD Install Video

This product is compatible with... Learn how to find your Mac's model ID
iMac Intel
iMac (27-inch Mid 2011)
(May 2011)
Model ID: iMac12,2
2.7GHz i5, 3.1GHz i5, 3.4GHz i7


  • (1) OWC Mercury Extreme Pro 6G SSD
  • (1) SSD Power Cable for 2011 27" iMac
  • (2) OWC 2-1/4" Suction Cup
  • (1) Torx T10 driver
  • (1) Torx T6 driver
  • (1) Phillips #2 driver
  • (1) Nylon Pry Tool (Spudger)
  • (1) iMac Adhesive tape set for SSD installation
  • (1) OWC Blue Microfiber Screen Cleaning Cloth

NOTE: This kit contains consumable and/or one time use components and therefore is non-refundable if opened. If you have any concerns about your ability to perform the upgrade, you can return the unopened kit for a refund.


The best warranty is one you never have to use - but should the need occur - we're proud to provide a superior level of support and service coverage to our customers.

5 Year OWC SSD Limited Warranty on the OWC Mercury Extreme Pro 6G SSD

Even when not used, we understand the peace of mind afforded by a longer warranty period. OWC's industry leading coverage is a testament to our confidence in the reliability of the solutions that we offer. OWC solutions are engineered to demanding quality standards in order to deliver the most reliable, highest performance available on the market in each storage category.

Customer Ratings

Write a Review 5 / 5 4 out of 4 (100%) reviewers would recommend this product
Verified Buyer
Reviewer: TheWriteThinker Location: Spokane, WA Age: 55-65 Experience Level: Home User Owned Product: 3-4 months
Rating: 5/5 Made me feel like an Apple Tech :D September 4, 2018 I've upgraded RAM in the past, and replaced an optical CD drive, but never attempted an advanced installation like this SSD drive required. OWC's installation video was excellent, allowing me to follow the instructions step-by-step (pausing and replaying the video often due to my inexperience) and complete the process in just under two hours. If I did this again it would take half the time but I didn't want to mess up my computer! The drive works flawlessly and my mid-2011 iMac 27" has been given a second life. Thank you, OWC!!!

I would recommend this item to a friend! This review is from DIY Kit for 2011 27" iMac's internal SSD bay: 1.0TB OWC Mercury Extreme Pro 6G SSD.. Customer Videos:

Verified Buyer
Reviewer: ronaldO Location: San Antonio, TX Age: 45-54 Experience Level: Home User Owned Product: less than a month
Rating: 5/5 Easy installation January 8, 2017 I upgraded my 27" iMac yesterday with the 1TB SSD. The tool kits helps with the installation! One thing to note is when you watch the installation video, he mentions using the included tweezers to help disconnect the connectors. I didn't have the tweezers included in my toolkit and they are not part of the toolkit I ordered. This was clearly an oversight on my part. My recommendation is to get tweezers for disconnecting connectors because big fingers don't work very well. The installation was straight forward and the video kept my on track. Computer works great and is much faster now!

I would recommend this item to a friend! This review is from DIY Kit for 2011 27" iMac's internal SSD bay: 1.0TB OWC Mercury Extreme Pro 6G SSD.. Customer Videos:

Verified Buyer
Reviewer: Anonymous Location: Navarre, FL Age: 55-65 Experience Level: Power User Owned Product: 1-3 months
Rating: 5/5 Best Upgrade June 11, 2016 My mid 2011 27" iMac is better then when new now that I've upgraded to SSD. I couldn't get the latest iMac to be as fast. Boot in under 20 seconds...used to take close to 2 minutes. All applications come right up. iTunes & Photo used to take forever with all the songs, video, and photos I have. Now is almost instant. I now will be keeping this computer for a long time. You can pay 4 to 5 times more for a new computer, or just upgrade your HDD to this SSD. Very happy with upgrade.

I would recommend this item to a friend! This review is from DIY Kit for 2011 27" iMac's internal SSD bay: 1.0TB OWC Mercury Extreme Pro 6G SSD..

Verified Buyer
Reviewer: Anonymous Location: Knoxville, TN Age: 55-65 Experience Level: Power User Owned Product: less than a month
Rating: 5/5 Flawless! I now have a brand new computer! May 12, 2016 I installed the OWC Mercury Extreme Pro 6G 1.0TB in my 12,2 27" iMac. After watching the videos, the installation went flawless. Here's how I did mine...

Before I started, I backed up the computer with Time Capsule just in case I needed it. I downloaded El Capitain OS X and had the Install executable in the Applications folder. Shut the computer down, install the drive per the video and powered up the computer. It booted into the old drive and I started Disk Manager. I formatted the new SSD. Next was starting the Install app, selecting the newly formatted drive for a clean install. After that was done, I used Migration Assistant and selected the old drive as the source and the OWC SSD as the destination. I let it do it's thing and 40 minutes later, my new SSD was bootable and FAST! After ensuring all was as it should be, I used Disk Manager to reformat the old 1.0TB drive for an internal back-up! While I had her apart, I installed 32gb of new ram. This computer is faster than new! I highly recommend OWC Drives and memory.

I would recommend this item to a friend! This review is from DIY Kit for 2011 27" iMac's internal SSD bay: 1.0TB OWC Mercury Extreme Pro 6G SSD..

DIY Bundle 120GB OWC 6G SSD and Internal SSD Kit for 2011 27" iMacs Mfr P/N: K27IM11SP120 OWC SKU: OWCK27IM11SP120 Complete DIY kit for adding an SSD to your 2011 27" iMac's internal SSD bay. 5 Year OWC Limited Warranty
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