I have an Optiplex 390 (actually 3 with similar behavior...).
PC would not power on. I did the power test and determine the Mobo was the issue.
I replaced the Mobo with a new one. Still can't power from front power button, but if I go at the back to the power supply 'power test button' and press on it the full PC comes on with all fans everything, but front power button is amber. And I get nothing on display, fans stay full speed. I can turn off, by pressing the from power button for a few seconds.
I tried using the CPU from another of the 3 PCs that had similar power issues and pointed to Mobo.
I reconnected all cables, tried different RAM modules, different video card, nothing makes a difference.
Not sure where to look now.
Assuming that you replaced the motherboard then it likely is the power supply has had it you'll need to buy a new one.
I do not work for dell. I am also a user.
SOLID AMBER POWER BUTTON = DEAD MOTHERBOARD
BLINKING AMBER POWER BUTTON = BAD POWER SUPPLY.
Power LED state
||Power is off, LED is blank.|
||Initial state of LED at power up.
Indicates system has power, but the POWER_GOOD signal is not yet active.
If the Hard Drive LED is off, it is probable that the power supply needs to be replaced.
If the Hard Drive LED is on, it is probable that an onboard regulator or VRM has failed. Look at the diagnostic LEDs for further information.
||Second state of the LED at power up. Indicates the POWER_GOOD signal is active and it is probable that the power supply is fine. Look at the diagnostic LEDs for further information.|
||System is in a low power state, either S1 or S3. Look at the diagnostic LEDs to determine which state the system is in.|
||System is in S0 state, the normal power state of a functioning machine.
The BIOS will turn the LED to this state to indicate it has started fetching operation codes.
I have no OLD led pattern.
I did replace the Mobo, and the new one allows me to see all fans, HDD, and DVD spinning.
Are suggesting my new Mobo is dead also. The initial Mobo was detected bad by doing the BIST power test (which is in the video), I was not able to see anything working, it was a major Mobo failure. Can I still have a dead Mobo and have all attached devices working properly?
You have No LEDs and no beeps at all cuz your motherboard is DEAD. There are 4 LED's on the Front.
Diagnostic LEDs for the OptiPlex series (2009 to 2012)
With this series, the diagnostic LEDs changed to include a combination of the Power button LED state and the diagnostic LED indicators. The Diagnostic LEDs remain 1, 2, 3, 4, and placed on the front of the unit. You could identify these system by their flat black and grey front face.
Have you considered failure of the front panel's circuit board and/or the mobo>front panel cable if both mobo give you the same issue? Or maybe even just a broken power button?
Forum Member since 2004
I'm not a Dell employee