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Hardware diagnostic testing
This section provides a more detailed approach to identifying a hardware problem and locating its source.
Caution! Before disconnecting any peripheral cables from the system, turn off the system and any external peripheral devices. Failure to do so can cause permanent damage to the system and/ or the peripheral devices.
1Turn off the system and all external peripheral devices. Disconnect each of device from the system, except for the keyboard and the video monitor.
2Make sure the system power cord is plugged into a properly grounded DC outlet.
3Make sure your video display monitor and keyboard are correctly connected to the system. Turn on the video monitor. Set its brightness and contrast controls to at least two thirds of their maximum ranges (see the documentation supplied with your video display monitor).
4If the operating system normally loads from the hard disk drive, make sure there is no disc in the optical drive.
5If the power indicator does light, attempt to boot from a disc.
6Turn on the system. If the power indicator does not light, see “Power indicator does not light” on page 132.
Verifying proper operation of key system lights
As POST determines the system configuration, it tests for the presence of each mass storage device installed in the system. As each device is checked, its activity light should turn on briefly. Check if the HDD activity indicator lights briefly? If not, see “HDD activity indicator does not light.” on page 133.
Confirming loading of the OS
Once the system boots up, the operating system prompt appears on the screen. The prompt varies according to the operating system. If the operating system prompt does not appear, see "No Characters Appear on Screen" on page 137.
