Power in motherboard but cant turn on

1) Computer off, unplug it from power.
Press the Power On button in, and hold it in for a count of 10 seconds.
Let go of the Power On button. Do this same procedure two more times.

This procedure clears CMOS Error Codes, and resets BIOS Setup, back to the factory default settings.

Plug the computer back into power, and monitor into motherboard.
(VGA connector,

http://en.wikipedia.org/wiki/VGA_connector )

WAIT 1 minute, turn the computer on.

No?

2) Computer off unplug it from power. Open the computer case.
FOLLOW Anti-Static Precautions.

Anti-Static Precautions:
Your body carries Static electricity. Static WILL fry out
(Short Circuit), the delicate hardware components inside a computer.

TOUCH an unpainted surface, of the metal frame of the open computer case. This action will relieve your body of Static.

SHOULD you leave your computer in the middle of working on it, be SURE to Touch the metal frame again upon your return.

Now remove the CMOS battery,

http://en.wikipedia.org/wiki/CR2032

Now press the Power On button in, and hold it in for a count of 10 seconds. Let go. Do this same procedure two more times.

Reinstall the CMOS battery. Plug the computer back into power.
Monitor to motherboard. WAIT 1 minute, turn the computer on.

Regards,
joecoolvette

The easiest way to check the board is to get a small screw driver and short 2 pins with it systamatically until the power comes on, give it a try, once you have found the 2 pins that turn the power on, find the power button connection and put it on the 2 pins you shorted with the scwrew driver, then test the switch at the front, it should now work.
Without the model no of the motherboard this is the only suggestion i can make. hope it helps and post back and tell me if you get it going. Jimnuggats.

it might be that it short circuited. try to remove the battery, unplug the ac adapter and press and hold the power button for about 15-20 sec to drain power. expect no response since we're just draining the power. then put back in the battery and ac, and try to turn pc on. if still no go, possible motherboard replacement.

The motherboard is probably bad for some reason. It works like this: you press the power button which sends a short to 2 pins on the motherboard requesting the power supply to turn on. If there is a short somewhere on one of the power leads then the powersupply cuts off automatically. This is why you see the fans start to run and stop. The power supply is probably good but the motherboard is bad.
You can test the power supply by placing a piece of wire, use a paper clip, between 2 pins on the power supply connector. Unplug the connector from the motherboard and look for the only GREEN wire in the connector. There will be a BLACK wire on each side of it. Using a paperclip, bend it and stick it into the green and one of the black wires pins. The power supply should come on with the fan running in the power supply.

Problems are possibly due to wires running through the hinges on the laptop which may cause a connection problem/short. Your right. Over time the hinges which house the wires from your screen to your motherboard can wear out causing the monitor wires to have shorts. You may need to contact a professional to replace the screen or to rewire the set.

There 3 possible problem with your board...
1. Processor
2. Ram
3. Bios

Check one by one

Sounds like either a short, or misconfigured cable connection.

That was pretty unclear.  Is there a kind of burning symptom that suggests a short to you?  It seems to me that what happened is that either there was a power outage and your system thus shut down...all you'd have to to would be hit the computer's power button to turn it back on...or a fan somewhere died and therefore the system won't power up until you replace or repair that.  At least get a vacuum in there and brush out the dust so you can work.

What happened when you got a simplified system that 'worked'?  Was the power supply's fan spinning, at least?  What's the green light on, anyhow?

it seams that the motherboard has some power problems. Check on the motherboard for burned or blackened components, or for capacitors that are looking like they are going to blow (inflated on the top), u can do the same to the power supply.
If so change it !
Also maybe the power of the house has problems that the computers power supply cant handle (that can ruin the motherboard or other components )
U can also try to isolate the motherboard from the case (there might be a short between the motherboard and the power supply through the case metal ... )