Released June 2012, Model A1278. Intel processor with Turbo Boost, Up to 512 MB DDR5 Video RAM

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How can I install OS X on a new ssd

I want to upgrade my macbook pros hard drive to a ssd but I don't want to use a back up as the ssd is going to be 250 gigs compared to my current 5400 drive that came initially with 500 gigs that has 226 gigs left on it. How can I do a fresh install of 10.11 with the new ssd in without a backup ? If you are wondering why I don't want to restore from a back up its cause the backups are too big and would fill the new drive full.

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First thing I would do here is make sure your systems firmware is upto date. Follow this Apple T/N: About EFI and SMC firmware updates for Intel-based Mac computers. You might have something still newer depending on your OS version.

  • Hint: the last digits (after the last dot) are hexadecimal so you'll need to convert it to decimal to know if your systems version is newer or older than the T/N. Mavericks and newer OS's have firmware updaters within the OS installer.

You'll need to get a SATA to USB adapter so you can connect your SSD externally to your system. Here's one unit: Startech 2.5" SATA to USB adapter for 2.5" drives.

With the SSD plugged in to your system you'll need to run Disk Utility to partition the drive with GUID and format it with Mac OS Extended (Journaled) partition.

The next step is to download from the Apps Store the OS installer.

Run the installer selecting the SSD drive it will install a fresh OS onto your SSD. Once done you'll want to double check if it's working correctly. Restart the system and press the Option key so you can select the SSD as the boot up drive. If the system starts up you can then shut down the system and swap over the drives. Follow this IFIXIT guide: MacBook Pro 13" Unibody Mid 2012 Hard Drive Replacement.

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Thank you Dan !!!!!


No problem! Let us know how it goes.


It worked perfectly, thank you for all!


"...The next step is to download from the Apps Store the OS installer."

Questions: Does the downloaded OS installer end up in your Applications folder? Then do you run the installer from there, but choose the newly formatted SSD as the install destination instead of upgrading your old OS on the internal HDD? Thanks.


Yes, the OS installer is placed in your Application folder. You'll want to copy it to your desktop or another folder as the installer in the Application folder will self erase after you run it from there.

This gets a bit confusing here as it depends on what you want to do. First make a full backup of your stuff (TimeMachine) On another drive. If you are swapping out your current drive and want to save your stuff you'll want to have both drives connected to your system. Then run the Installer to first formatting your new SSD and then install the OS (hint: use a new user account name). At the end it will ask you if you want to migrate your user accounts, Apps and data over. If you want to limit what is transferred either clean things up before hand or limit your folders as you want to move over.

I would strongly recommend you also replace the HD cable and place some tape under the cable that rubs against the upper case.


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Just a note if you have problems.

Apple will replace the hard drive/IR cable on this particular model for free, no questions asked.

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