Sony Vaio laptop won't start

[Easyb]

I have a Sony Vaio laptop VGN-S5HP/B.
When I press the power button, the power and battery LEDs flash then go off. The WLAN light flash as well.No noise (cpu fan in this case) is heard.The computer won't start then...
I have removed the battery and tried with the adapter only but the same occurs. I even changed th RAM but nothing works.
Any help is appreciated

 

[Tmagic650]

Remove the battery and AC Adapter. Press and hold the power button for 2 minutes. Plug in the AC adapter and see if the computer turns on normally. If not, the laptop will have to be serviced