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Lançado em junho de 2012, modelo A1278. Processador Intel com Turbo Boost, até 512 MB DDR5 de RAM vídeo

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93% CPU usage caused by kernal_task

It's very slow and pinwheels on every task, even just opening system preferences. I checked the cpu usage and it is pretty much pinned at 93% kernal_task being the cause. Anyone have an idea of what could be causing this? I've tried smc and pram clearing. MacOS reinstallation. I've also bought seagate firecuda sshd and cloned my oem hdd and installed that with no change in performance.

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First I don't recommend cloning. In days past it was a very useful method but todays OS's it tends to mess things up. In addition when you have SATA cable breakdown which I suspect it your issue here any errors on your original drive will past over to your new drive.

Follow this IFIXIT guide to replace the HD SATA cable: MacBook Pro 13" Unibody Mid 2012 Hard Drive Cable Replacement and here's the cable you'll need: MacBook Pro 13" Unibody (Mid 2012) Hard Drive Cable. In addition you'll want to put down some electricians tape on the uppercase where the cable rests.

Once you have the cable installed you'll need to wipe the drive down and re-install the partition and format it. Using either internet recovery or if you have a bootable OS installer USB thumb drive (the faster method).

Once your drive is up and running use Apple's Migration Assistant to copy over your stuff


MacBook Pro 13" Unibody (Mid 2012) Hard Drive Cable Imagem


MacBook Pro 13" Unibody (Mid 2012) Hard Drive Cable


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I know hard drive cable failure is pretty common but would it really cause the kernal_task to like max out my cpu?


Surprisingly yes! The drive and your CPU are in a battle. Think of it this way you go to a library but you can't pick the book off of the self you need an attendant to do it for you but he constantly pulls the wrong book so you send him back over and over again! In truth the issue is what we call Cyclic Redundancy Check (CRC).

You can prove this by booting up on an external drive.


This did not fix my issue.


Did you reformat the drive and re-install a fresh copy of OS from the OS installer?

Lastly, don't use the clone copy! Instead use the Apple Migration assistant. While its slower it will make sure the files are in good shape when they are moved over.


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