Hi,

I have Precision 5510. Last week, after it was left to sleep, I can never boot up again.

At first, it was not plugin to power cord, when I try to turn on the laptop, the power button LED just light up white for around 1 second and light off.

Then I tried open laptop and change CMOS battery. Still the same thing.

Next I followed steps to drain electricity by unplug battery and power cord. Pressed power button for 30 seconds, and plugged in power cord and battery. Still the same thing.

Then I tried remove RAM, HD and bluetooth. No luck either.

As I read more, I understand my laptop is in no POST state with power button and LED under mouse pad flash white light every 1-1.5 seconds. This is with power cord and battery plugged. I tried to start the diagnosis mode by pressing and hold and power button. At first you can see keyboard lights on and fan spinning, then it stops after 3-4 seconds, the LCD never turns on.

Does anyone has any suggestions or know what part is broken? Any help is appreciated.