Troubleshooting 75
Power Lights
  CAUTION: Before you begin any of the procedures in this section, follow the 
safety instructions in the Product Information Guide.
The power button light located on the front of the computer illuminates and 
blinks or remains solid to indicate different states:
• If the power light is blue and the computer is not responding, see 
"Diagnostic Lights" on page 76.
• If the power light is blinking blue, the computer is in standby mode. Press 
a key on the keyboard, move the mouse, or press the power button to 
resume normal operation.
• If the power light is off, the computer is either turned off or is not 
receiving power.
– Reseat the power cable into both the power connector on the back of 
the computer and the electrical outlet.
– If the computer is plugged into a power strip, ensure that the power 
strip is plugged into an electrical outlet and that the power strip is 
turned on.
– Bypass power protection devices, power strips, and power extension 
cables to verify that the computer turns on properly.
– Ensure that the electrical outlet is working by testing it with another 
device, such as a lamp.
– Ensure that the main power cable and front panel cable are securely 
connected to the system board (see "System Board Components" on 
page 103).
• If the power light is blinking amber, the computer is receiving electrical 
power, but an internal power problem might exist.
– Ensure that the voltage selection switch is set to match the AC power 
at your location, if applicable.
– Ensure that the processor power cable is securely connected to the 
system board (see "System Board Components" on page 103).
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