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iBook G3 – are 12" and 14" logic boards compatible?

Ivan Holmes

New member
Hi,

A few months ago I bought an iBook G3 12" (A1005) in non-working condition off eBay UK. The original logic board had the usual graphics fault so I have purchased an iBook G3 14" logic board as a replacement. Other than the different battery connector (the 14 inch connects to the battery via a daughterboard), they appear to be exactly the same. I soldered the correct battery connector (from the daughterboard) on to the 14" logic board, fitted it and booted the machine.

The output on the screen is a real mess - I'll upload a video later but it basically goes from black, to grey, to black again and then various single pixels turn red, green and blue.  

I've noticed that the screen is a bit bulged near the bottom where the inverter sits, so I think it may actually be faulty, and the pattern on-screen looks more like a faulty LCD than graphics chip to me. The pattern also plays itself out in that sequence whether the machine has booted from cold, booted from hibernation, booting OS X, booting OS 9, etc – it seems to be completely unrelated to what's actually on screen. 

When plugging in an external monitor via the mini-VGA port, the output is perfect, so the graphics chip definitely works.

What I'm really asking is: will an iBook G3 14" motherboard drive an iBook G3 12" display?

I have an actual A1005 motherboard coming in the post so I guess I'll find out for myself soon enough, but if anyone has any wisdom to share it'd be much appreciated.

Thanks,

Ivan

 

Franklinstein

Well-known member
They're mostly the same but the battery connection is different: the 12" has the battery connector directly on the logic board while the 14" has a connector with an extension board that connects to the battery. Also the heatsinks may be a bit different (14" longer than the one in the 12") but those should be swappable, unlike the battery connector.

 

Ivan Holmes

New member
I resolved the battery connector issue by soldering the battery connector from the extension board on to the logic board. That aspect of the conversion works absolutely fine. 
My main issue is whether the display connections between 12" and 14" are compatible? I've had a look online and nobody has said anything either way. 

 
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