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Have a mid 2012 Macbook pro (2.9ghz, 13inch) I have a 850 Evo in the optical drive. Whenever i try and install a new OS it crashes mid way through the install. (Currently running Seriria and have been for a number of years on the SSD) I have tried a fresh install of the OS and formatting the SSD with no luck so far. The original HD drive in the original bay has never shown up since I installed the SSD in the optical drive. I suspect i need a new SATA cable but just want to check. Also would I need to change the SATA cable on the HDD and the Optical drive caddy SSD? Or just the HDD one? Thanks
You should have the SSD in the main bay with the Mac OS installed onto there. Then on the secondary optical bay use the HDD there because it’s only SATA 2 on the optical bay if i remember correctly.
@Sam B - Are you running the installer from your HDD drive? If you are then the HD bay SATA cable is the root issue here MacBook Pro 13" Unibody (Mid 2012) Hard Drive Cable follow this guide MacBook Pro 13" Unibody Mid 2012 Hard Drive Cable Replacement You’ll also want to place a strip of electricians tape on the uppercase when the cable crosses over and you’ll want to use an old BIC pen ink straw (empty) to use as a forming brake to create nice round arcs where the cable needs to be bent. You don’t want sharp folds as that damages the cable.
