Dell 390, GH458 manual Replacement.For instructions on, Modules are installed

Light Pattern	Problem Description	Suggested Resolution
	No memory modules are detected.	1	Reseat the memory modules to ensure
			that your computer is successfully
			communicating with the memory.
		2	Restart the computer.
		3	If the problem still exists, remove all
			the memory modules and install one
			memory module in memory module
			connector 4.
		4	Restart the computer.
			The following message appears:
			Alert! Operating in Debug
			Mode. Please Populate
			Memory in Pairs for Normal
			Operation.
		5	Press <F1> to boot to the operating
			system.
		6	Run the Dell Diagnostics. See page 34
			for instructions.
		7	If the memory module passes, shut
			down the computer, remove the
			memory module, and then repeat the
			process with the remaining memory
			modules until a memory error occurs
			during start-up or diagnostic testing.
			If the first memory module tested is
			defective, repeat the process with the
			remaining modules to ensure that the
			remaining modules are not defective.
		8	When the defective memory module
			is identified, contact Dell for a
			replacement.For instructions on
			contacting Dell, see your User’s Guide.
		NOTE: If necessary, the computer can
		operate in debug mode until new memory
		modules are installed.
	System board failure has occurred.	Contact Dell for technical assistance.
		For instructions on contacting Dell,
		see your User’s Guide.

40

Quick Reference Guide