●Check the Power LED on the front of the computer to see if it is flashing red. The flashing lights are error codes that will help you diagnose the problem. Refer to Appendix A, POST error messages on page 236 for more information.

●Turn up the brightness and contrast controls of the monitor if the monitor is dim.

●Press and hold any key. If the system beeps, then the keyboard should be operating correctly.

●Check all cable connections for loose connections or incorrect connections.

●Wake the computer by pressing any key on the keyboard or pressing the power button. If the system remains in suspend mode, shut down the computer by pressing and holding the power button for at least four seconds then press the power button again to restart the computer. If the system will not shut down, unplug the power cord, wait a few seconds, then plug it in again. The computer will restart if it is set to power on automatically as soon as power is restored in Computer Setup. If it does not restart, press the power button to start the computer.

●Reconfigure the computer after installing a non-plug and play expansion board or other option. See Solving Hardware Installation Problems on page 220 for instructions.

●Be sure that all the needed device drivers have been installed. For example, if you are using a printer, you need a driver for that model printer.

●Remove all bootable media (CD/DVD or USB device) from the system before turning it on.

●If you have installed an operating system other than the factory-installed operating system, check to be sure that it is supported on the system.

●If the system has multiple video sources (embedded, PCI, or PCI-Express adapters) installed (embedded video on some models only) and a single monitor, the monitor must be plugged into the monitor connector on the source selected as the primary VGA adapter. During boot, the other monitor connectors are disabled and if the monitor is connected into these ports, the monitor will not function. You can select which source will be the default VGA source in Computer Setup.

CAUTION: When the computer is plugged into an AC power source, there is always voltage applied to the system board. You must disconnect the power cord from the power source before opening the computer to prevent system board or component damage.

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