The Pane Startup

The pane Startup is designed to manage special settings of the operating system or of the computer’s firmware, which won’t affect normal operations, but only the startup phase of Mac OS X.


Mac OS X is supporting different startup modes that can be preconfigured with TinkerTool System:

Attention Starting the system in safe mode will also clear nearly all system and user caches. This will slow down the startup phase significantly and —due to the empty caches— will also slow down the subsequent operation of Mac OS X. Keeping safe mode on for longer periods of time does not make sense and should be avoided.

Mac OS X uses a horizontal progress bar to indicate the extremely long startup in safe mode.

When using Mac OS X 10.6 or 10.7, the operating system comes with two alternative kernels: The conventional kernel in 32 bit architecture, and an additional kernel in 64 bit technology. The system will automatically select the recommended kernel for your computer model at boot time. If you are not satisfied with the selection, you can enforce a manual selection of the kernel. Select one of the options at System Kernel. Note that your computer will automatically ignore selection of a 64 bit kernel, if either the CPU is not capable of using 64 bit code technology, or if Apple has explicitly blacklisted your computer model for 64 bit operation. The current operation mode of the kernel and the 64 bit capabilities of your computer can be verified via the Info pane of TinkerTool System.

Apple does not allow that specific “non-pro” computer series can run the 64 bit kernel. OS X Mountain Lion no longer supports 32 bit kernels and drivers, so this option won’t be displayed when using version 10.8 or later.

Using a 64 bit kernel might disable certain device drivers and kernel extensions, in case they are not available in 64 bit technology yet. Note that operation of the kernel is independent of user applications. Mac OS X will automatically run applications with 64 bit technology if the applications and the processor are supporting this, even if the kernel is running in 32 bit mode.

Power Control Options

If the option Wake for network access is enabled in the computer’s Energy Saver settings, OS X usually makes use of the function Bonjour Sleep Proxy to automatically wake the computer when another computer accesses a public network service of the sleeping computer. (Please also see the detailed description in the section Network of the pane System.) If the network service is not being accessed directly, but a standard Wake On LAN (WOL) signal is sent to the sleeping computer, it might happen in the latest versions of OS X that the computer does not awake completely, but only partially, keeping the monitor off (“dark wake”). This can be sufficient for many remote maintenance features, but it is often desired that the sleeping computer should be powered on completely. In addition, technical problems with certain third-party software products can be avoided.

Startup options
Startup options

By selecting the option Enforce full power-up when receiving wake signal over network (no “dark wake”) you can ensure that the system kernel should perform a conventional, complete wake-up when a WOL signal comes in.

Another power control feature is available via the setting Enforce pre-Lion behavior regarding power control of monitors. New functions, which Apple had introduced with Mac OS X 10.7, and which control the power management of displays, will be deactivated intentionally.

The detail behavior of this setting can be changed by Apple in each version of OS X without notice. Some users had positive results with this setting when using OS X 10.8.1 by keeping the internal display of a mobile computer off, even when the display lid is opened, if an external monitor, keyboard, and mouse are connected. However, we won’t guarantee any specific functionality of this startup option.

Diagnostic and Developer Settings

Additional options are available for diagnostic purposes:

The generated NMI signal is actually not a true Non-Maskable Interrupt, but an ACPI System Control Interrupt (SCI).

To use one of the listed options, perform the following steps:

  1. Open the tab item Options of the pane Startup.
  2. Activate or deactivate the listed options as desired.


Users can individually set the languages they prefer when working with applications. This personal preference setting is controlled by the priority list displayed at International > Language > Languages in System Preferences. However, this setting only affects applications started by each user, it does not apply to the startup phase of the operating system and its login screen, situations where no user has logged in yet. Under normal circumstances, this additional language preference can only be set when installing the operating system.

Startup language
Startup language

TinkerTool System allows you to modify this language preference without having to reinstall the system. Perform the following steps:

  1. Open the tab item Language of the pane Startup.
  2. Select the preferred language with the pop-up button Startup Language.

This will also change the keyboard layout used when running the login screen. If you don’t own the keyboard type typically used for the selected startup language, it may become difficult to enter user name and password correctly.

Under certain circumstances, the startup language setting of Mac OS X can have been damaged, e.g. when you have restored your system from a Time Machine backup. In this case, TinkerTool System will display an additional button with the option to repair the setting.

Chime (Mac OS X Snow Leopard only)

Before the startup of the operating system begins, all Macintosh systems perform a self test and use a chime signal to acoustically confirm that the computer appears to function normally. Because the sound signal can be extremely loud and is not really needed in most cases, many users want to disable this feature.

TinkerTool System can mute the startup chime to solve this problem. To do this, perform the following steps:

  1. Open the tab item Chime of the pane Startup.
  2. Set a check mark at Suppress the startup chime.

If you have additional operating systems on your computer which are not Mac OS X, this feature may not always work correctly, because the other systems may reset the computer’s startup sound configuration each time they are being used. Because TinkerTool System cannot run on other systems, it cannot prevent this. If you are running multiple copies of Mac OS X only, you can solve this problem by activating the startup chime suppression feature in each of the installed systems.

The function to switch off the startup chime is a feature of TinkerTool System, not an actual preference setting of the operating system. For this reason, the check mark can only reflect the current status of TinkerTool System’s function, not that of other applications which might also offer a sound suppression feature. It is not recommend to use two or more different programs that try to manipulate the startup chime. The applications could work against each other, creating unpredictable results.

Startup chime
Startup chime

The startup chime is played by the firmware of the computer, so it is not directly dependent on Mac OS X or TinkerTool System. During the installation of firmware updates, or the installation of a new operating system, the startup chime may be reactivated by the firmware. TinkerTool System will automatically correct this, the next time the system is performing a start/shutdown cycle under normal operation conditions.

The startup chime is not needed to detect hardware errors. Although the sound signal confirms that the system has successfully passed the self test, switching off the signal does not mean to switch off the test. Errors will still be reported by a diagnostic code and the system will be halted in case a hardware problem has been detected.