Raust Jinx

Flashing amber light on the motherboard

A friend recently brought me his Optiplex GX520 to have me look at it.  He couldn't get it to power on and also said that he had a lightening strike just outside his house.  And from the conversations that I have had about his surge protection, well, there really was none.  The power was still plugged in as well as the cable for his internet.  I have tried a known working power supply in his machine, but the problem was not resolved.  There is no response when the power button is pressed and no lights on the front of the machine will illuminate.  There is, however, an amber light in the lower left corner of the motherboard, labeled Aux Pwr, that flashes on and off when the power cord is plugged into the power supply.  When removed, the light stays illuminated for approximately 7 seconds, until the power supply is totally drained. 

My idea is that the motherboard is no good and needs replaced.  I have removed all the components, including the RAM and battery, just to be sure there was no other components causing the issue, but still nothing.  The computer is about 4 yrs old, so I am suggesting to him a new machine, specially since he really doesn't need anything too powerful or expensive, just something to check email and view pictures on.

Any other suggestions would be much appreciated.

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Re: Flashing amber light on the motherboard

 Raust Jinx

The LED on the motherboard is the 'Stand By Power Light' [aka 'flea power'] and only indicates the motherboard has 'some' power reaching it, not an indication that the power supply has not failed.

Are any of the four diagnostic lights Lite?

Are there any 'Beeps'?

.If you are comfortable working around computers, you could try the following:

Note: The only 100% method of testing a PSU, is to install a know working power supply.

Unplug the cord from the power supply, hold the power button in for about 15/20 seconds, open the case, unplug the 24-pin power connector from the motherboard and jump the Green wire to one of the Black wires, reconnect the power cord and power the system, if power supply's fan and the hard drive run, then the PSU should be good.

Note: Do not remove any wires from the plug, use a small piece of wire or a paper clip as a jumper.

Power supply checks out and the system still does not work, again remove the power cord, hold the power button in for several seconds to discharge the residue power, reconnect the 24-pin connector to the motherboard.

Remove all the PCI cards, the video card [if applicable], memory, all peripherals, disconnect the data and power cables to all the drives, check that the front panel cable is connected to motherboard, with nothing else connected to the system, reconnect the power cable and power the system on.

If you do not get any beep codes and/or there is no change in the diagnostic lights, then it would appear that the motherboard has died.

Lightning strikes at a minimum usually take out the Modem or NIC.

If the damage is bad enough to require a motherboard, consider replacing the system.



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