I have MacBook Pro Mid 2012 and a MacBook Pro 2010. I wanted to upgrade both to internal SSDs. The 2010 works great with a SSD but the 2012 will not boot from an SSD. I bought two SSD and set them up with High Sierra. Both SSDs work fine when placed in the 2010, but neigher will boot the 2012 when placed in it. My old HD still works fine in the 2012 so I know the HD cable is working. Why will the SSDs boot the 2010 MBP but not the 2012???
TitanJim wrote:
I did order a new SATA cable. Will see if that helps. I don't understand how if my original cable is bad why the internal hard drive still works fine when I reinstalled it???!!!
The SSD requires a much higher quality cable than a hard drive because an SSD transfers a lot more data across the cable so any slight defect in the cable will cause issues transferring the data to an SSD. I have had some of our organization's 13" (mid-2012) MBPros install macOS just fine, but then is unable to boot to the clean install on the internal drive. The difference between the install process and booting directly to the internal drive that data is going in one direction during the install (to the SSD) and when booting the system is reading & writing to the drive. Think of a single lane road. All traffic goes one way so it flows more easily than traffic moving in both directions. The more traffic and the faster the traffic is moving the more difficult it is to navigate that same road. I have seen these cables fail in multiple ways with many different symptoms. It is possible you had problems with this cable but never realized it when using the much slower hard drive since a bad cable can make a perfectly healthy hard drive run extremely slow.
Also Apple at one time had a free repair program to replace the hard drive SATA Cable on the 13" (mid-2012) model where Apple would proactively replace the cable even if the system appeared to be working fine. That is the only time in 20+ years that I have known Apple to proactively replace a part that appeared otherwise functional. The cable failure is so common that Apple felt it was necessary to replace the cable whenever this particular laptop model was repaired. Unfortunately the free repair program has expired.
You've almost confirmed the failure yourself. The only other reasons for the new SSD not work in the 2012 laptop is either you have a Logic Board failure or the SSD is not compatible with that laptop. Since the SSD works fine in a much older Apple laptop a compatibility issue is unlikely and a Logic Board failure for this type of issue extremely rare. Plus this cable is the easiest and least expensive option to explore.
TitanJim wrote:
I did order a new SATA cable. Will see if that helps. I don't understand how if my original cable is bad why the internal hard drive still works fine when I reinstalled it???!!!
The SSD requires a much higher quality cable than a hard drive because an SSD transfers a lot more data across the cable so any slight defect in the cable will cause issues transferring the data to an SSD. I have had some of our organization's 13" (mid-2012) MBPros install macOS just fine, but then is unable to boot to the clean install on the internal drive. The difference between the install process and booting directly to the internal drive that data is going in one direction during the install (to the SSD) and when booting the system is reading & writing to the drive. Think of a single lane road. All traffic goes one way so it flows more easily than traffic moving in both directions. The more traffic and the faster the traffic is moving the more difficult it is to navigate that same road. I have seen these cables fail in multiple ways with many different symptoms. It is possible you had problems with this cable but never realized it when using the much slower hard drive since a bad cable can make a perfectly healthy hard drive run extremely slow.
Also Apple at one time had a free repair program to replace the hard drive SATA Cable on the 13" (mid-2012) model where Apple would proactively replace the cable even if the system appeared to be working fine. That is the only time in 20+ years that I have known Apple to proactively replace a part that appeared otherwise functional. The cable failure is so common that Apple felt it was necessary to replace the cable whenever this particular laptop model was repaired. Unfortunately the free repair program has expired.
You've almost confirmed the failure yourself. The only other reasons for the new SSD not work in the 2012 laptop is either you have a Logic Board failure or the SSD is not compatible with that laptop. Since the SSD works fine in a much older Apple laptop a compatibility issue is unlikely and a Logic Board failure for this type of issue extremely rare. Plus this cable is the easiest and least expensive option to explore.
If you have the 13" (mid-2012) model, then the internal hard drive SATA Cable is most likely bad. This cable has an extremely high rate of failure on this specific model especially when used with an SSD. Even if you have a 15" or 17" model the cable could be bad.
https://eshop.macsales.com/search/?q=hard%20drive%20cable&filter.catidpath=3406
We've done the SSD upgrade on three 2012 MBPs and always used Carbon Copy Cloner to clone the old drive to the new one. We've kept the same pattern: Put the SSD in a USB3 enclosure for formatting and cloning. CCC very nicely prompts you to create the important recovery partition on the new drive. Only after System Preferences > Startup Disk confirms that the SSD is bootable do we move the SSD to the MacBook Pro.
And we always installed a fresh cable. +1 on HWTech's sage assessment.
What brand of SSD?
just guessing. "I bought two SSD and set them up with High Sierra" Did you do both installs using the 2010? If so, not a good idea.
I used recovery mode on the mid 2012 MBP to format and install. Drive verification in Disk Utilities said they were fine. But they would not boot in the mid 2012...just got the gry circle with slash through it. They booted fine when placed in the 2010 MBP!!!!???
I did order a new SATA cable. Will see if that helps. I don't understand how if my original cable is bad why the internal hard drive still works fine when I reinstalled it???!!!
MacBook Pro Mid 2012 won't boot from internal SSD
