Mac OS 9, Mac OS X: Press X key during startup to select Mac OS X on single-volume installations
Summary
If Mac OS 9 and Mac OS X are both installed on the same volume, you may press and hold the X key during startup to select Mac OS X. This article applies to PowerPC-based Macs only.
The "volume" in this case is an unpartitioned hard disk. The "startup volume" is simply the volume that contains the active copy of the operating system. Startup Manager allows you to change the startup volume on the fly by pressing and holding the Option key during startup, but it only displays one operating system per volume. This means you cannot use it to switch between Mac OS 9 and Mac OS X in the default configuration. You could, however, use it to choose between your internal hard disk, a FireWire hard disk, and a CD-ROM disc.
Products Affected
Mac OS 9.0, Mac OS X 10.4, Mac OS X 10.3, Mac OS X 10.2, Mac OS X 10.1, Mac OS X 10.0, Mac OS X 10.5
When to use the X key instead of Startup Manager
Use the X key instead of the Startup Manager when these conditions exist:
- Both Mac OS 9 and Mac OS X are installed on the same volume (the default configuration).
- The computer last started up from Mac OS 9.
- You want to switch to Mac OS X during startup.
Follow these steps:
- 1. If the computer is shut down, press the power button. If it is on, restart it.
2. Immediately press and hold the X key. The computer starts up to a gray screen, then restarts again.
3. Release the X key after the computer restarts.
The computer starts up from Mac OS X. The Startup Disk setting is now changed to start up in Mac OS X. This differs from using Startup Manager, which does not save the preference change.
Additional Information
For more information and scenario-specific solutions, see:
Startup Manager: How to Select a Startup Volume
Startup Manager: Only Displays Mac OS 9, Not Mac OS X
Startup Manager: Only Displays Mac OS X, Not Mac OS 9