Dell U7021, WHL Error exists Requirements exist see, Your computer see, Occurred, Conflicts see

Light Pattern			Problem Description	Suggested Resolution
			No memory modules are detected.	• If you have two or more memory
					modules installed, remove the
A	B	C	D		modules, reinstall one module (see
					page 77), and then restart the
					computer. If the computer starts
					normally, reinstall an additional
					module. Continue until you have
					identified a faulty module or
					reinstalled all modules without error.
				•	If available, install properly working
					memory of the same type into your
					computer (see page 77).
				• If the problem persists, contact Dell
					(see page 131).
			Memory modules are detected, but a	• Ensure that no special memory
			memory configuration or compatibility		module/memory connector placement
A	B	C	error exists.		requirements exist (see page 76).
			D	• Verify that the memory modules that
					you are installing are compatible with
					your computer (see page 76).
				• If the problem persists, contact Dell
					(see page 131).
			A possible expansion card failure has	1	Determine if a conflict exists by
			occurred.		removing a card (not a graphics card)
A	B	C	D		and restarting the computer (see
					page 80).
				2	If the problem persists, reinstall the
					card that you removed, remove a
					different card, and then restart the
					computer.
				3	Repeat this process for each card. If
					the computer starts normally,
					troubleshoot the last card removed
					from the computer for resource
					conflicts (see page 64).
				4	If the problem persists, contact Dell
					(see page 131).

= yellow = green = off

Advanced Troubleshooting

55