It sounds like you have power to and in the system and it's getting to the battery so that's not the problem here.
The fact your not hearing the bong or seeing any activity on the display is starting to look like the logic bd has gone.
Swapping the RAM around is not the first thing I would do in this case as it could add a new problem if the SIMM's aren't fully seated after you put them back. Besides, you would have gotten a memory error if one of the SIMM's were bad.
Did you get your system wet or drop it?
- It could have been a while ago when it got wet and the moisture has slowly corroded some of the connections.
- If you banged the system you could have pinched a ribbon cable or wire depending where the case is dented.
The next step is opening up the system and making a careful inspection for anything out of place corrosion or something pinched. Carefully tug slightly and push back in the connectors to make sure they aren't loose and are making good contact.
Lastly, disconnect the internal HD and plug in an external HD (Firewire) that has Mac OS-X on it. If you don't have a HD to do this still pull the internal and see if the display comes up with a question mark icon. If that happens your HD is dead and it's sapping all of the power so the rest of the system can't run.
If your still not getting any display (look carefully as may not to lit by the light source in the display) then the logic bd. is blown. If you see an image but the display is not lit the display light source has a problem.
In both cases there's little one can do other than replace either or both which will be costly.
Good Luck!
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Still had no luck, anyone else got any ideas? Cheers!
by MSJ
What charger to you have? If you have a newer one does the connector LED Green or Orange.
Try running the system without the battery, any luck that way?
If you put your ear to the system do you hear any internal sounds (HD or fan) when you depress the power button?
by Dan
Hi Dan,
I bought a new charger about 6 months ago (and a new battery), initially the led stayed green but I unplugged it for a while and now it's orange. The LED's on the battery indicate it's charging and about to hit full charge.
When I depress the power button I hear the whirring sound that normally precedes the 'dong' sound when the computer starts up, and the fans appear to be on and running normally.
by MSJ