That way you’ll be able to tell if your battery really is performing less well after upgrading. IBook G3 300MHz 320MB Tangerine Clamshell, running OS X 10.3.9. PowerBook Lombard G3 333MHz 512 MB, running OS X 10.3.9. Powerbook Pismo with G3 400MHz 768MB, running Linux MintPPC 11. Powerbook Pismos with G3 500MHz 1GB, running OS 9.2.2, OS X 10.3.9, and/or OS X 10.4.11 with Classic Mode OS 9.2.2. The 10 must-have utilities for macOS Sierra For the least frustration and most efficiency on your Mac, install these handy extras. Rename the USB flash drive to “Sierra.” (Note: the drive name should be the same within the corresponding command, if you change the drive letter name, you must make sure that the name. Open “Applications → Utilities → Disk Utility” and then “Erase” (format) the USB flash drive into “Mac OS X Extended(Journaled)” format. When you upgrade to High Sierra, the installer offers to upgrade your disk to APFS during installation. An option lets you format disks so that encryption is built in, not merely applied as it is in Apple's FileVault.
