Using Apple Hardware Test
You can use Apple Hardware Test to help determine if there is a problem with your
To use Apple Hardware Test:
Disconnect all external devices from your computer except the keyboard and mouse.
If you have an Ethernet cable connected, disconnect it.
Insert the Mac OS X Install Disc 1 that came with your computer.
Restart your computer and hold down the D key as it starts up.
A list of available startup volumes appears.
Click Apple Hardware Test and click the right arrow.
Follow the onscreen instructions when the Apple Hardware Test main screen appears
(after about 45 seconds).
If Apple Hardware Test detects a problem, it displays an error code. Make a note of the
error code before pursuing support options.
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 the Mac OS X Install Disc 1.