To use AHT, you must boot from the AHT CD using the same procedure used for starting up from any CD. That is, insert the AHT CD into the optical drive on the system that you need to check, choose Restart from the Apple menu (Mac OS X) or from the Special menu (Mac OS 9), then press the C key until the Mac displays a small “loading” icon.
It takes about a minute or so before the Apple Hardware Test window appears. Notice the three tabs: Apple, Hardware Tests, and Hardware Profile. The Apple tab reveals information about AHT, such as the version number. By default, the Hardware Tests tab is active.
The Hardware Tests tab provides the following buttons:
Quick Test conducts an abbreviated hardware ...