New SSD Installed in a Mac® Computer Is Booting Slowly

After upgrading the storage drive on a Mac® to an SSD, on rare occasions the new drive is not automatically set as the Startup Disk. This means the Mac system will sit on the grey start screen for an extended period before starting to boot the OS. This situation is can be easily corrected:

  1. Select System Preferences
  2. Click on Startup Disk
  3. Click on the newly installed SSD and select Restart

The Mac computer will now start booting from the SSD as soon as it's powered on.

If your SSD is slowing over time this is typically due to it not receiving Trim commands. Performance can be restored with the drive's Garbage Collection feature.

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