The screen freezes.
ÂForce the application that has frozen to quit. Choose Apple () > Force Quit and select the application.
ÂIf that doesn’t work, force the computer to restart by pressing the power button on the front of your computer for approximately 5 seconds.
The light on the front of the display is flashing.
On some Apple
ÂIf you see a repeating sequence of three short flashes, the display is detecting input in the wrong video format. Make sure your display is compatible with your graphics card and that you’ve installed the correct display software, if your display came with installation software.
ÂIf you see a sequence of two short flashes and a long flash, the display is detecting a problem with a backlighting lamp. Contact an Apple Authorized Reseller or Service Provider.
Using Apple Hardware Test
You can use Apple Hardware Test to help determine if there is a problem with your computer’s hardware.
To use Apple Hardware Test:
1Disconnect all external devices from your computer except the keyboard and mouse. If you have an Ethernet cable connected, disconnect it.
2Insert the Mac OS X Install Disc 1 that came with your computer.
3Restart your computer and hold down the Option key as it starts up.
A list of available startup volumes appears.
4Click Apple Hardware Test and click the right arrow.
5Follow the onscreen instructions when the Apple Hardware Test main screen appears (after about 45 seconds).
6Make a note of the error code before pursuing support options.
If Apple Hardware Test detects a problem, it displays an error code. If Apple Hardware Test does not detect a hardware failure, the problem may be
For more information about Apple Hardware Test, see the Apple Hardware Test Read Me file on Mac OS X Install Disc 1.
Chapter 4 Troubleshooting
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