I carried out a repair on an iBook G4 12" 1.2Ghz. I have documented as this is the 20th successful repair of it's kind. A long time ago I read a pdf document from a European company that had extensively investigated the iBook G4's with 'failed graphics chips'. (Mentioned in the May 4th, 2007 news page here in a post titled Examination Report on some iBook G4 Vreg. solder joints cracking over time. Some iBook G3's also had a problem with the GPU chip (BGA) solder joints cracking from board flex - some tried reflowing the solder, others used chip compression (which may not be a permanent fix but BGA reflow is not something most home users can do). As mentioned here in the past, a couple companies also offered iBook G3 repair services (reflowing the BGA solder joints).-Mike)
In their lengthy document they had several microscope images of what they found to be the cause. One of the images showed the solder connections on a particular chip on the logicboard. It gave clear evidence that at least one of the pins on this chip was prone to breaking free. I happened to have two duff iBooks on the shelf and proceeded with an investigation of my own.

I opened the iBooks and investigated this chip. I used the point of a dental pick to probe each of the 28 pins. A gentle nudge on them confirmed that they were securely soldered - all of them were except one (pin # 28). (Check Pin 1 carefully also, as it's another likely candidate for solder joint problems.) I thought I saw a minute amount of movement on that one. I dug out my Sherlock Holmes magnifying glass and, sure enough, it did move. The soldering iron was fired up and I tried to re-solder the pin by simply applying enough heat to melt the existing solder. It worked. The iBook sprang to life and ran perfectly for a couple of days. However, it reverted to it's problem state.
(To help prevent the flexing/cracked solder joint problem from reoccurring, I'd try either a (non-conductive) support shim for the chip or better yet (IMHO) use non-conductive Epoxy on each end of the chip to secure it to the board. That hopefully would make it less likely to flex/crack a solder joint again. (As with the iBook G3's (BGA) GPU chip problem, some have also used (non-conductive matl.) shims on top of the chip in an effort to compress any cracked solder joints into firm contact, although often that's not a permanent fix.) None of these methods may be a permanent/long term fix for this problem. However if Apple won't repair/replace the logic board, at least this may get it working again for some period of time.-Mike)
I tried to re-solder again but made a mess of it by trying to apply a tiny amount of solder to the pin. I ended up soldering 3 pins together :-) (Apply heat (small tip iron) to the pwb pad and once hot, touching solder to the pin should reflow the joint w/o bridging other pins. If the pin (or pwb pad) is severely damaged from repeated repair attempts, overheating/too high a wattage iron, etc., tacking a bus wire to the pin/board pad is another option (and properly done would have some 'flex' in the wire).
But personally, first I'd try just reflowing the suspect solder joint and then Epoxying the chip to the board (filling end gaps).-Mike)

However, on the second duff laptop I had I decided to try something different. Plan 2 worked well. In fact, it has worked so well that I have repaired a further 19 laptops with only one of them coming back to have the job done again. Here are the details.

Pic 1 - The exposed underside of the iBook Logicboard. I have highlighted the chip in question.

Pic 2 (below) - The chip fully exposed, pin with solder crack on bottom side, far right. (Pin 28 {VCC} - opposite the Chip's "dot", which denotes pin 1.-Mike)

Pic 3 - A small section of copper exposed adjacent to pin 28. Scraped off varnish (solder mask/conformal coating) with a small flat tip screwdriver. (But hopefully you can just reflow the pin's solder joint and then secure the chip without needing to do this)

Pic 4 - The solder repair.

I would love to know if anyone manages to resurrect an iBook of theirs!
-Best Regards,
Kevan G.
-> Fix My Mac <-
www.fixmymac.co.uk

The current (as of May 2008) iBook Exchange/Repair Extension Programs page only shows two iBook G4 (12in) Battery exchanges (Aug 2006 and May 2005), although I knew I'd mentioned a Logic board repair extension program a few years ago - I searched and found an old page from Dec 2004 on Expanded iBook (G3) Logic Board Repair Extension Program FAQ. However the iBook G4 vreg issue hasn't been addressed to date at least (and likely never will).-Mike

Reader Feedback on iBook G4 Vreg Solder Joint Repairs:

(added 6/23/2008)
"Hey Mike, After trying the shimmy and touching the solder tip on the legs, 8 months later the iBook died again. So I found this page and tried (the above) repair of scraping to the copper and adding solder. It's alive again, and I don't know how long it'll live, but since i purchased it 4 years ago, if I can get 1 more year I'll be more than happy. Besides, it's my teenage step-son's iBook so it's not that big a deal. How lucky is he to have a mom that can solder? Hubby thinks I'm nuts...but I'm just a geek :)
... And by the way. I had a solder gun from a computer fix kit, but no solder. I found some old electronics (speaker), reheated the solder, used a precision knife to scoop up some flow, and used that little ball to resolder pin 28. I burned the chip below that a little bit :( But it still works! Thanks a bunch!
-Fernanda"

If you've done a repair, Mod or Upgrade to your Mac you'd like to share, let me know. Thanks.-Mike