Sounds like the motherboard.
I have a Dell Latitude D640 which does not come on.
With AC connected I press the power button some lights come on as if it's going to start but then I hear a faint click and everything goes off. I tried this with and without the battery.
I disconected the AC, held the power button down for a minute and still no joy.
What should I try now?
Thanks,
Nathan

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