Dell Precision M4600 (Early 2011) - Manual (Page 139)

Diagnostic LED Error Description
Blinking
Solid Solid The microcontroller is handing control of the
system to the processor. This code persists if no
processor is detected.
Solid Blinking Solid The memory has encountered an error.
Blinking Blinking Blinking A system board component is faulty.
Blinking Blinking Solid The video card is preventing the system from
completing POST.
Blinking Blinking Off The keyboard is preventing the system from
completing POST.
Blinking Off Blinking The USB controller encountered a problem during
initialization.
Solid Blinking Blinking No SODIMMs are installed.
Blinking Solid Blinking The LCD encountered a problem during
initialization.
Off Blinking Blinking The modem is preventing the system from
completing POST.
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