'''Sounds more like HD damage''' than VGU (the MBD appears pooched, except for the repair partition).''Connect to an external monitor'', if that's working it could be a bad cable/inverter/LCD. ''LEDs tell you nothing about the HD, '' only about the power supply and video chain.
LED #3 will be ON when the computer is communicating properly with the video card. '''If LEDs 1 and 2 are ON and you heard the startup sound, but LED 3 is OFF,''' then the video card might be installed incorrectly or need replacement.
LED #4 will be ON when the computer is turned on and video signal is being generated. '''If the LED is ON and there is no image on the LCD display panel, the LCD display panel or inverter might be installed incorrectly or need replacement.'''
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