I have a 12" Apple PowerBook G4 that I ordered on eBay a while ago. The seller listed the laptop as perfectly working, however it is anything but. It has issues, which I think are the result of a bad GPU, but I can't be totally sure. It really only works once it has had a chance to warm up. What happens is that there are lines all over the screen, distorted graphics, weird fuzziness and colour changes. It always crashes when the graphics are distorted. But because of this, I have a hard time trying to get it running. I already opened the cover on it and it no longer reacts to physical motion, but I still haven't been able to determine the cause of this issue. I already posted about this on MacRumors, but I still have not been able to determine the cause. Does anyone here have any suggestions? It is not software related at all, as a clean installation of Mac OS X and entering the Open Firmware interface will still display these issues.
If it's crashing then yeah it's probably the CPU chip (it has the graphics in it), whether this is due to overheating or not I can't say as there's not enough information. I'd contact ebay about it as it's false advertising.
It's a bit late for the eBay claim. Because the laptop was purchased on my mother's eBay account, she would be dealing with it, but due to the confusion and the fact that it does work but with difficulty getting it started, she didn't start it. I have been suggested to that the solder joints may be weakening, and to me, I think this was further proven by how I started it with the top cover off and pressed onto the heatsink with a screwdriver the display atrocities would either weaken or disappear completely, and when I removed pressure they'd come back. But I cannot reflow it. I don't have the proper tools or skills to do such a thing.
It's not overheating, but I think that the general wear has caused it to begin to come loose. As I said above it only works when it's warm. If it's cold it has trouble running. Actually I'm not even sure that I mentioned that now that I think about it. Hope I don't sound rude. :icon_wink
when things heat up they expand, so if the heat sink only connects to the cpu when it's getting warm then that might be why it seems to get better as it runs.
That, now that you mention it may be totally possible. When I took off the top cover and pressed onto the heatsink and the problem improved or disappeared completely, it may have been making full contact when I did so. However, I only pressed onto the lower part of the heatsink. The G4 processor is located at the upper part.
Ok I have to set my way back machine for the mid 2000s. What speed is it. It is a 800MHz to 1GHz? IIRC those had issues with the solder joints on the GPU chip. The use used a BGA package and basically the little solder balls about come lose and the GPU would quit working. If you have the right equipment it can be reflowed. ( I have done it myself with a hot air gun but my success rate was about 50%) I have also heard of people putting shims under the logic board to put pressure on the GPU to fix the issue also. Apple was not the only one with this problem, just about everyone had this issue. Basically the boards were not supported well enough and would flex and crack the joints. Now the other issue I recall from this time periods is the solder joints would break on the lower DIMM slot, but I think that was just on the 15" and 17" 1.5GHz models. I don't think it impacted the 12" --edit I tried to send you a PM but can't as you are a regular member. There is another forum I know of that focuses on old 68K Macintosh, but have expanded to PowerPC apple gear as well that could help you out, but I don't think I am allowed to post the link.
This is an 867MHz 12" PowerBook G4. I'm having the feeling too that the GPU is either not making full contact on the heatsink or the solder joints are starting to break or come loose. I have heard that people have solved similar issues by baking the logic board in the oven, and I've even watched a YouTube video of someone doing the same thing with a Power Mac G5 logic board that had similar issues. The same thing could be said about my iMac, which also has a failing GPU. But what does worry me about my iMac (It's a late 2006) is that the 24" 2006 iMacs also had defective GPUs and the GPU could be replaced as it was slotted on the logic board and this solved the issue for some people. So in the iMac it is probably the GPU itself, and not failing solder points/poor heatsink contact.
On your iMac does it have the NVIDIA 8600GT graphics? If so NVIDIA had a run of defective GPUs in 2006/2007 where the die would separate from the heat spreader killing the GPU. NVIDIA had to pay for a lot of replacement parts on that one. I had the logic board in my 2007 MacBook Pro replaced by Apple as part of the extended warranty a few years back, but I think that program expired in 2012 or 2013.
No, mine is a 20" which has the ATI X1600 GPU. I'm not sure what causes that one to have issues, but I know it is a heat aggravated issue. Luckily you can disable the GPU by removing the .kext file corresponding to the GPU in the Extensions folder in the System folder. This will make the computer work but it will be slower.
It sounds very similar to the logic board issues on the old G3 iBooks. It's a matter of aiming a heat gun at the GPU, at a low temperature.
I don't have a heat gun. One friend of mine and I were going to reflow it a while ago, but we couldn't figure out how to open it. I know how to open it now, but I don't have the right screw driver to unscrew the display cable from the logic board. That's as far as I've ever gotten with opening it.
Why not take it to the apple store? And a G4? Wow... I wouldn't have personally wasted the money on a PowerPC Mac. I've had my share, PowerPC and even a few Motorola 68K based Macs... If it is of value, I'd take it to the store. I myself am not good with soldering... poor fine motor skills. I don't see the point of even owning a PPC based Mac anymore.
I highly doubt the Apple Store is even going to service it because of its age. They might determine the issue but they won't fix it. They're not going to have the parts on hand. I bought it because it was another system that I wanted to add to my collection. I paid $23.50 for the laptop. I'd never pay $100+ for something old like that. Personally I think that G4s can still do Internet browsing and email and you can use YouTube if you have a YouTube client like MacTubes. You don't have to have one, but I do like to have the G4s as a part of my collection. I don't use them very often, but for those that I do (my Power Mac G4) I have some older games I play on them and I can use Facebook among other things on them. Plus there is still a lot of older creative software that can still be used, albeit less capable than newer versions.
Assuming that, I guess it isn't too urgent, then. I used to collect computers... I had an Apple 2GS, a few apple computers with a Motorola 68K Processor, at one point someone gave me a DEC Alpha Workstation... My collection was all thrown out.
