When the computer is turned on, it does not complete the power on self-test (POST) process, there is no image on the display screen, and the Power On indicator LED is blinking green (or blinking blue on some models). The blink pattern is ON for one second, OFF for one second.

1. Hold down the power button for approximately 10 seconds until the computer turns off.
   
   
2. Verify that neither one of these keys are stuck in the down position: 
      
         the Tab key (arrows pointing left and right)
     
         the tilde key ( ~ and ` characters)
   
   
3. Turn the computer on.
   
   
4. If either of the keys above appears to be stuck in the down position, and if the issue is not corrected by pressing these keys repeatedly, then service is required.

See also these Support Bulletins on related topic:

98080952 Computer will not turn on

94000234 No Image on LCD display

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