How to tell if a laptop motherboard is dead.

[ArashT]

So i found this laptop laying around. It died one year ago.
When i press the power button nothing happens. No lights, sounds, fans, nothing.
So i took it apart, tried to boot it up with one stick of ram at once, but still nothing.
I decided to order a power board with the apposit cord and power button, but again, it refuses to turn on.
I tried different ac adapters, still nothing.
Tried to power it on with just the battery plugged in, and guess what, nope.
Tried removing the cmos battery for a while, or even holding the power button for 1 minute with everything unplugged.
So I'm pretty sure it's the motherboard failing (no evident damages on the board), but I'm also afraid that the cpu could cause this problem.
So the question is, are those the symptoms of a dead motherboard or a dead cpu?
Again, i tried different sources of power compatible with that mainboard.
And no, i don't have any spare parts to test things out sorry.
Thanks for your responses.

Oh and sorry for my sloppy english.

 

[maxwellmelon]

no power up sounds like motherboard. if the cpu was bad you would see a quick flash of the power led before it sat there and did nothing or shut right back off. im guessing its a power realted issue and unless it has a separate power regulator board in it most laptop power control is built into the motherboard. the bigger question is it even worth fixing.

 

[ArashT]

Thnk you or your reply.
Another thing I noticed: the led indicating that the battery is being charged (or fully charged) doesn't light up at all. That probably means that the motherboard is infact not working right? Would that led show up if the motherboard was working but not the cpu? Thank you

 

[maxwellmelon]

if the charge led is not lighting up it does help confirm that the PMC (power management circuits )on the laptop motherboard is bad. The PMC control the power to the battery from the ac adaptor and also control the power from the battery to the motherboard. The only other possibility is the ac adaptor is bad but you said you had a way to check that so im down the MB.

 

[ArashT]

Thank you very much for your quick responses, I appreciated your help