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I have a Macbook Pro and my problem is that when I hit the power button it seems like it’s going to turn on and I can hear the sound of the fan, the cd-rom and also the hard drive start if I keep the power button pressed down. Once I release the power button, the computer shuts down. If I just press and release the power button the light indicator just flashes as if it wants to start, but it shuts down immediately. I already tried everything on the Apple troubleshooting page from taking off the battery and disconnecting the magsafe cable, to pressing the Ctrl-Comd-Power button, but nothing has worked. Any one who could help to find out whatthe problem could be. Also, my computer is out of warranty, so please help me to find what is wrong instead of telling me to take it to the Apple store.
In your situation what you want to know is if the logic board is the culprit or not since a logic board replacement can be really expensive and you might prefer to sell the machine for parts instead of repair it. What I will suggest as troubleshooting steps is technical stuff and you may not be prepared to do it yourself but for the benefit of those who can, here is it. If all the preliminary troubleshooting steps (PRAM, SMC reset, ram test, etc) have been tried to find the problem without success I would take off the battery, remove the MBP top case, disconnect optical drive, hard drive, airport card, bluethoot cable, well all cables that can be disconnected from the logic board without prevent it to power and boot to the screen question mark . Once everything is disconnected from the LB connect the ac adapter and try to power by tripping the two power pads on the logic board. If the logic board boot to the question mark then it should be good and the culprit is probably something currently disconnected that’s causing the problem.
I may write a book on your problem but not right now. We seldom recommend going to the Apple store unless we believe it free, all they say is “you need a new logic board”, and you just might. I hate that “I’ve tried everything”, but let’s assume you have. How’s the caps lock button after it appears to shut down? Did you press it? How does it run with just one RAM chip? What’s it look like on your external monitor? How are the lights on your battery? What color is the MagSafe adapter? Did it tone when you zapped the PRAM? What’s the history on this machine? Repairs?