Another A1181 fails to boot - logic board?

[limeybrit]

Here are the symptoms:

Macbook is receiving power from the charger & charges the battery
When Power button is pressed, fan starts, optical & HDD are heard to spin up & heads seek.
The LCD briefly flickers, but remains black, with no image visible via a bright flashlight aimed at the screen
There is no chime, the keyboard (inc caps lock) is unresponsive & the sleep LED is solidly lit.
Whilst the USB ports are powered up, attached external keyboard/mouse are unresponsive.
No signal is present on the mini-DVI output.

Repeating the powerup sequence after removing the optical & HDD drives appears to make no difference.
Doing so after removing the RAM does cause the sleep LED to blink rapidly.
Removing the battery before powerup doesn't change the outcome.
Swapping in an alternate HDD/RAM appears to make no difference. Tested the swapped RAM on an intel core duo iMac and was OK.

So, is this likely the oft-mentioned logic board failure, or is there something else I should try?

 

[Bustycat]

I have the similar issues from my MacBook1,1 and I can’t think about any other reason rather than a logic board failure.

 

[rampancy]

I've got a couple of A1181s in my parts bin that have this issue; it's clearly a logic board failure (unless you get the warning beeps, which is more indicative of RAM issues).

 

[Applicator]

@limeybrit @rampancy just out of curiosity: What generations are those dead-LB A1181? Is it a certain incarnation or a general issue? I've never seen a dead A1181 without the influence of water or excess force (and I've seen quite a few).

 

[rampancy]

@limeybrit @rampancy just out of curiosity: What generations are those dead-LB A1181? Is it a certain incarnation or a general issue? I've never seen a dead A1181 without the influence of water or excess force (and I've seen quite a few).

In my extensive experience, the dead A1181 motherboards I've encountered met their end through liquid damage and general use/misuse. I haven't encountered anything to suggest it's an endemic issue with a specific model generation.

Apart from that, I have encountered one or two working MacBook 1,1s and 2,1s with failed RAM slots, but at this point I'd ascribe that to age issues like cracked solder joints.