To help you troubleshoot a problem, your small form factor, small desktop, and small mini-tower computers have four lights labeled "A," "B," "C," and "D" on

the back panel. The lights can be yellow or green. When the computer starts normally, the patterns or codes on the lights change as the boot process

completes. If the POST portion of system boot completes successfully, all four lights display solid green. If the computer malfunctions during the POST process,

the pattern displayed on the LEDs may help identify where in the process the computer halted.

NOTE:

The orientation of the diagnostic lights may vary depending on the system type. The diagnostic lights can appear either vertical or horizontal.

Y = Yellow

G = Green

Light Pattern

Problem Description

The computer is in a normal off

condition or a possible pre-BIOS

failure has occurred.

A possible BIOS failure has

occurred; the computer is in the

recovery mode.

A possible processor failure has

occurred.

Memory modules are detected, but

a memory failure has occurred.

A possible expansion card failure

has occurred.

A possible graphics card failure

has occurred.

A possible floppy or hard drive

failure has occurred.

system board may be faulty or incorrectly installed.

A power supply or system board failure has occurred.

A problem was detected while the BIOS was executing.

The monitor or the graphics card may be faulty or

incorrectly installed.

An integrated system board device may be faulty.

Suggested Resolution

Plug the computer into a working electrical outlet and press the power button.

Run the BIOS Recovery utility, wait for recovery completion, and then restart the computer.

Reinstall the processor and restart the computer.

If you have one memory module installed, reinstall it and restart the computer. (see "Memory"

for instructions on how to remove and install memory modules.)

If you have two or more memory modules installed, remove the modules, reinstall one module,

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.

If the problem persists,

Determine if a conflict exists by removing a card (not the graphics card) and then restarting the

computer.

If the problem persists, reinstall the card that you removed, remove a different card, and then

restart the computer.

Repeat this process for each card. If the computer starts normally, troubleshoot the last card

removed from the computer for resource conflicts (see

Incompatibilities").

Move each card one at a time to a different PCI slot and restart the computer after each move.

If the problem persists,

If the computer has a graphics card, remove the card, reinstall it, and then restart the

computer.

If the problem still exists, install a graphics card that you know works and restart the

computer.

If the problem persists or the computer has integrated graphics,

Reseat all power and data cables and restart the computer.

complete.

Check the