XPS/Dimension 400/9150 yellow light blinking at power button, computer will not come on. Inside Motherboard has a green light on it. Please advise issue.

A steady or Amber blinking power button indicates a low voltage problem. This can be caused by a defective power supply or a defective motherboard. Just to make sure that nothing else is causing the problem, remove any PCI cards like modem, video card, sound card, etc... Remove the memory modules and disconnect cables to CD/DVD drives. Look at the USB ports to see if any are damaged.

Have you checked to see if your power supply is still good, or the power supply connection to the motherboard is good?

A solid green light means the computer is operating normally.

A solid yellow light indicates the power supply is operating normally but the computer is not processing data.

This could mean there is a problem with the CPu or another component on the motherboard.

((A blinking yellow light indicates the power supply is receiving power from the wall, but not functioning properly.
This generally means the power supply itself is bad and should be tested or replaced.))

A blinking green light means the computer is in standby mode.

You should consider visiting Dell Support and downloading the manual for your

your Dell computer. So use the LED power light codes if your Dell computer has them.

hope this helps

Contact technical assistance.They will most likely ask you to send it back to repair.

This chart is where I got my conclusion.

Power Light

Problem Description

Suggested Resolution
Solid green
Power is on, and the computer is operating normally. On the desktop computer, a solid green light indicates a network connection.
No corrective action is required.
Blinking green
The computer is in the suspended state (Microsoft® Windows® 2000 and Windows XP).
Press the power button, move the mouse, or press a key on the keyboard to wake the computer.
Blinks green several times and then turns off
A configuration error exists.
Check the diagnostic lights to see if the specific problem is identified.
Solid yellow
The Dell Diagnostics is running a test, or a device on the system board may be faulty or incorrectly installed.
If the Dell Diagnostics is running, allow the testing to complete.
Check the diagnostic lights to see if the specific problem is identified.
If the computer does not boot, contact Dell for technical assistance.
Blinking yellow
A power supply or system board failure has occurred.
Check the diagnostic lights to see if the specific problem is identified.
Solid green and a beep code during POST
A problem was detected while the BIOS was executing.
See "Beep Codes" for instructions on diagnosing the beep code. Also, check the diagnostic lights to see if the specific problem is identified.
Solid green power light and no beep code and no video during POST
The monitor or the graphics card may be faulty or incorrectly installed.
Check the diagnostic lights to see if the specific problem is identified. See "Video and Monitor Problems" in your Owner's Manual.
Solid green power light and no beep code but the computer locks up during POST
An integrated system board device may be faulty.
Check the diagnostic lights to see if the specific problem is identified. If the problem is not identified, contact Dell for technical assistance.

if the system will not power on, I would suggest a new power supply as the first troubleshooting option as they are about 1/3 the price of the motherboard. The Flea Power indication on the motherboard only indicates power is reaching the board, not if all needed voltages are being received.
Normally on a Dell, if you are getting power then when you attempt to power on, you usually get a power LED indication on the power button. Solid Green/Blue is normal, Flashing Amber is Power supply bus failure, Solid Amber is normally a motherboard.
If you haven't bypassed the UPS and connected direct to the outlet, I would try that 1st, as the UPS could be the failure too.

I suggest replacing the memory as the diagnostics lights suggest.
Memory can and does fail in some cases.

• Blinking Amber/yellow: 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.

A Blinking Amber or Yellow power button means that the power supply is receiving power from the source but is unable to properly distribute it to the components. This can be caused by a defective power supply or a defective motherboard. Just to make sure that nothing else is causing the problem, remove any PCI cards like modem, video card, sound card, etc... Remove the memory modules and disconnect cables to CD/DVD drives. Look at the USB ports to see if any are damaged.


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Unplug computer, disconnect all usb/monitor/internet, open it, hold power button until green led on the inside on the motherboard turns off, pop out the BIOS battery (looks like a big watch battery and use a small flathead screwdriver to depress the spring lock on one side), plug in computer, hold power button for about 20 seconds (must reset BIOS or something), let up on power button, wait 10 seconds and push power button. The computer should turn on. Wait for it until activity seems stable (1 min. or so). Push powerbutton to shut off.

If this has worked you have proven that it's not the power supply (it turned on).

Go buy a new battery (CR2032 3 volt). Unplug computer, open it, hold power button until green led on the inside on the motherboard turns off, pop in new battery, plug in (you should notice the power button blinking amber again), hold power button until it stops blinking (about 20 sec....again must reset BIOS or something), wait 10 sec., push power button. the computer should turn on. Wait for it until activity seems stabe (1 min. or so). Push powerbutton to shut off.

Now, close case, plug in all usb/monitor/internet/etc. Power up computer. You'll get an internal floppy drive error. Push F2 (maybe F1) to get into the BIOS settings and go to "drives" and turn off the internal floppy. Save and exit. The computer should boot properly now.

This seems to be a big problem with the e510, my theory is that this one small battery is the root of most of these failures (as these computers usually fail after 1-2 years), not the power supply or the motherboard (heck, when you replace the motherboard it comes with a new one of these batteries...a several hundred dollar piece of hardware, with a $5 battery that will actually fix it).

Please read and try this offered procedure.