I have been having a terrible time with signal dropouts and failures to connect to my wireless router after updating my G3/900 iBook to 10.4.3.

My RAM slot is dead as well. 15" 1.5 Ghz Powerbook

I have two 1.25 GHz Powerbooks, I just realized that one of them has this problem, the other is fine. Thank goodness for Apple care.

For Trevor, yes this can happen, and is seems like it is happening.

No problems here..... G4 15" Aluminum (first generation), shipped from the factory with two 256MB chips, replaced one with a 1GB for a total of 1.25GB. Everything's been happy, and I've had it two years now.

Gee...I found my dual 1.8 G5 was missing 1/2 its memory last night. Never thought to blame OS X updates! Actually, I pulled all the ram and reinstalled. All came back after this. Maybe someone should try this on a PB if they are having issues.

Interesting... I've lost the use of my lower RAM slot in a 15" PB 1.25GHz. Happened somewhere in the early 10.3 range, but I never considered an OS update as a possible cause, and have no way of backtracking to investigate now.

I work as a service repair technician and can confirm that the lower ram slot seems to fail on a regular basis on the Powerbook G4 15.2" 1GHz and up.

However, I have absolutely no belief that it is caused by a software update. Nearly every case that I've seen was not a result of a software update, and I have done in the neighbourhood of a dozen or more of these replacements. I believe this to be a defect in the logic board design rather than a software update issue, and really, if you look at the range of updates that people are suggesting that cause this issue, you have to wonder what could possibly be similar in ALL of those updates that would cause a memory controller failure in this fashion. I have also seen the outer slot fail in the same way as the inner slot, so it is not isolated to that particular area.

It just happens that software updates get blamed for most problems when, in my experience, it is due to some other outside but completely unrelated problem with the machine. A corrupted directory structure is a very common one that people seem to have when they claim that a software update 'crashed' their system and it won't boot afterwards. A quick DiskWarrior scan of the drive fixes it, I reinstall the OS, and I look like a hero. Of course, we're not talking about a software problem here, but it seems very strange that, once again, the software update process is being blamed for another problem.

While I wouldn't call this a common problem, it is certainly one I have seen a number of times on these units. The most common failures are still white spot LCD panels, superdrives, and hard drives.

I just looked on my 1.25 Ghz 15" and sure enough, the lower slot RAM is not working, and system profiler says there's no RAM there. The machine came to me with the standard 2X256 mb RAM.

Since upgrading to 10.4 all my machines have suffered kernel panics often. This never happened under 10.3 My Graphite iMac, powerbook 15" 1.25ghz and my MDD machine, crash constantly! I would say that 10.4 is probably the worst version ever of OS 10. The iMac crashed twice on wake from sleep today alone. The MDD crashes in the middle of the night constantly and the powerbook gives me a black screen instead of waking from sleep every now and then. This never used to happen with 10.3 It is interesting to see others have the same problem. It seems as if the Mac community has been tight lipped about this until now. I hope that Apple reads the crash reports, mine have not been very nice.

My TiBook 400 lower memory slot recently went down as well, although I cannot link it to a software update. Currently running 10.4.3.

Without going in to all the details... SW can absolutely induce a HW failure. Writes to firmware, voltage parameter instructions, etc. Obviously not intentional meatheads.

Wha? I just checked and sure enough my 15" 1.5 GHz PB is showing only 1 GB of ram and I have 2 of the 1 GB chips installed. Running 10.4.3 and have done all of the updates. Even scarier - my warranty expires 1/13/06 and I detest paying for an additional warranty. Freakin hell - now I have to go to my local Apple Store and see what they say...

I have worked in large software/hardware system testing for a few years now I propose you can easily have software causing (or exposing) a harware problem. I have seen problems where the hardware spec was not being met but was not discovered until a software change (tighter timing, smaller.larger que, etc) exposed what had been flaky hardware all along. The way to test this is to go back to the old SW and see if the hardware works again. Be sure all software is back to the way it was (firmware, PRAM settings, etc) There could be a lawsuit if Apple was shipping non spec hardware that was not exposed until 10.4. I am not saying this is the case, only that a relationship is possible.

I had this exact problem upon updating to 10.4.1 and took it to the genius bar. They fixed in within about 10 days (while wiping the HD along the way.)

BE CAREFUL HOW YOU PICK UP YOUR POWERBOOK.

If you pick it up so it flexes (such as by one corner), eventually the pins on the bottom slot come loose. I had this after 9 months. Motherboard replaced under warranty. I've been careful how I pick it up since then, no repetition after a year. It doesn't happen to the 12" because they're not heavy enough to flex much, and I think most 17" owners use both hands anyway because they flex *a lot*.

Trevor,
it seems likely that *this* failure is not caused by software. To say that software cannot cause failure is not completely accurate. I've certainly been warned many times not to over-hz-ify my crt display, and had one smoke when i deliberately did it anyway to avoid flicker.

i've seen a core stack burn up while running pattern tests.

i've seen mainframes of more than one manufacturer fail with memory related problems simply because they referenced memory too quickly - backing out the update in those cases restored full functionality.

just because these are relatively old examples doesn't mean it can't happen again, at least in my opinion.

My TiBook seems perfectly happy.

-jfg

I don't really think that this is a "software causing hardware damage" kind of situation, but it certainly does not require god-like powers. The WRT54G router I have uses software to control the output power of the analog amplifier (probably a single CMOS transistor. The default value is 29 and the range runs from 0-255. As I push it beyond 45-50 I can feel the transistor heat up quite quickly and I am almost positive that If I just type in something much higher and click apply I WILL damage the hardware beyond repair. This is a very simple situation, but I am very sure that the same thing is possible with any hardware that relies on the laws of thermodynamics to function. I would bet that a simple mis-calculation in kernel space could fry the processor in any of our Macs by ramping the fans down instead of up when cycling the CPU or video card.

Laurence

Actually it is not the RAM slot that goes bad it is something else in the RAM controller. You will find that if you have 1 chip installed in either slot, then the computer will recognize it, however as soon as you install 2 chips the lower slot is not recognized. I was a MG at an Apple store when this issue first started popping up - I was actually the first tech to escalate the problem to engineering, and may have been the first to see and diagnose the issue. It has nothing to do with a software update, although software updates will often show issues that have been there all along - such as faulty RAM that worked great in Panther, but will give kernel panics in Tiger. This is not a problem with the software, but while Panther may have been more tolerant of faulty RAM, Tiger is not. The same is true with this faulty RAM controller, I saw the issue with Panther as well as Tiger, but it is more frequent with Tiger, because of the way Tiger access the controller, and is less tolerant of the fault. Jason

Trevor, you are an idiot.

Software CAN damage hardware. Your theories of laws of physics and such are juvenile and ignorant at best.

I'm not saying that specifically in this case the OS X updates are causing the RAM slot issue. But your blanket statement that software cannot damage hardware is just plain wrong.

Any hardware that has firmware can be screwed over royally by a firmware upgrade.

For example: Firmware for DVD player. DVD Drives typically are set for a specific region, but allow that region to be changed a few times for convenience sake. Software could quickly render that DVD drive incapable of playing any DVDs.

Same can be said for hard drives (causing them to stop working). Ever flashed a video card? You will find LOTS of discussions on the net about people trying to flash video cards and causing them to stop working.

I think I've said enough.

Fifteen inch 1.25 PB: Five months ago, I had the Apple store in London repair what, at the time, seemed to be a screen issue. They ended up replacing my screen.

When I got the computer back, it still wasn't working right. For starters, it had lots of sleep issues. When I put it to sleep for the night, it would come on periodically and always be hot in the morning with the fan running. And almost always, when I'd try to wake it, I'd have to do a hard restart. Then too, as time went on more and more frequently it froze: again, I had to do a hard restart.

So near the end of November, I took it in to my local Apple certified repairman. He had it for a month as he looked for a secondhand logic board to put in. But not finding a logic board easily, he initialized the hard drive and installed a clean system. Then he ran it--for eighty hours, he said--with no crashes or problems.

So he called me and suggested I try it again; maybe the problem was gone?

I picked it up and tried it and had few problems for the first day or two. So, because with my growing iPhoto database, my 756 of RAM wasn't cutting it, I bought a new gig DIMM from Memory4less. The minute I installed it I had nothing but constant kernel panics--and right at startup, never later. So I went to BestBuy and bought a different gig DIMM, Kingston brand.

Again, I put it in and had nothing but kernel panics, constantly and right at startup. Returned it and got a different DIMM from the same store, same brand--Kingston. Same problems.

Because I had not yet returned my Memory4Less DIMM, i then experimented with ever possible configuration of the four chips I had: one 256 Samsung original to the PB from Apple; one 512 DIMM I purchased a couple years ago from Memory4Less; one gig from Memory4Less purchased in late November; and one gig from BestBuy purchased a couple weeks ago. I tried each DIMM with every other DIMM, each one in each slot--both bottom and top. No matter what I did with the one gig DIMMS, I had nothing but constant kernel panics. When I replaced the original 256 DIMM and the later purchased 512 DIMM, I had the fewest kernel panics and could, at least, use the PB--although it was very unstable and had lots of power managing and sleep issues. But it only froze occasionally (once ever hour or so).

Then, I read this discusssion and tried one last thing: I pulled out the old 512 DIMM from Memory4Less and placed the original Apple/Samsung DIMM in my upper slot, leaving the lower one empty.

BINGO! It's been rock-steady ever since. But ssssslllllllloooooooooowwwwwwww!

So now what? Any suggestions? I'm out of warranty and wonder whether if I managed to find a new one gig DIMM that didn't have the slewing issues the two others have, apparently, whether I might live happily ever after despite having one empty slot. What do you all think?

There is too much arguing going on here, the fact is there is an issue. I don't care what caused the issue, I just want mine fixed. Apple needs to address the issue. Software, hardware, don't care. In fairness, to most people it would seem to be a software glitch, especially since I can boot up with Apple Hardware Test, run the tests, all check out at 100% (both slots and my RAM) but then I go to bootup and the system crashes or doesnt recognize the lower slot all of a sudden. Seems to me if the hardware test doesnt find any errors with it, OS X should be able to see it ok too.... apparently not.

I had the same problem. 15" Powerbook 1.25Ghz aluminum -- 2GB of RAM became 1GB of RAM. I bought a new set of matching 1GB SODIMMs to replace what was in the machine, then realized after experimenting with it that the DIMMS were not to blame. I eventually bought a new 1.6Ghz powerbook to replace it. It was a good machine except for the missing 1GB.

I have had this problem before I did the 10.3.9 update (I havent bought 10.4 yet) I have a 15" 1 Ghz used to have 768 Mb of RAM now I'm only on one 512 chip. Pro Tools doesnt really like to run on 512 so I've been screwed for about a year now since I mostly use it for mobile recording anyway. I shouldve sprung for the AppleCare. Oh well. Maybe they'll do a replacement thing like they did with the batteries, which my PB was a part of as well. I still will get a PB over a Dell any day, these are just minor setbacks. I just wish these problems weren't so costly.

I have a similar problem with my 15" 1.5 GHz, and I haven't upgraded to 10.4. Currently I have a 1 Gb SO-DIMM in the lower slot - nothing in the upper slot - and my machine is unable to boot.

Has anyone had any luck simply moving a single SO-DIMM from the lower slot to the upper slot?

My 2 year old PB lost the lower memory slot last fall. I ordered a 1gb stick from Crucial.com and placed it in the top slot with no problems. However, when trying to put it in the lower slot, system would hang. Now I have a dormant 512 in the lower that I hope will someday be recognized again...

Chris, you should be able to move a good memory stick from the lower slot to the upper, just make sure you seat it firmly.

Same here. Not on the lucky list and have a semi-functional lower slot. If I have ram in both slots is says lower slot empty. If I have only 1 stick in the lower slot it sees it. If I then put in the other stick, lower slot empty again. Pah! what a lemon. Should have kept the 12in.

Hi everyone:

Just wanted to reply to the comments about whether there was a possible lawsuit to pursue. There is, but I don't know much about it or how it works. The website has all this info, and you have to decide whether or not this is for you.

The website is

http://www.lawyersandsettlements.com/case/apple_powerbook_classaction

I had been using with no problems a 15" 1.5 GHZ with two kengsinton 1GB SODIMMS installed.

I won another one (same model) in a contest; took out one of the 1GB SODIMMS out of the older one and installed it alongside an old 256 memory card I had removed from the older one when I purchased the two 1GB cards.

After installing the memory I I checked "About this Mac" and System profiler and it showed the new memory installed, no problems (1.25 GB)

After aprox. 2 hours of testing this machine by running a memory-intensive video app I started to notice slow performance.

I Checked the system profiler. The lower slot was reported empty.

I opened and changed the cards from place (the 1GB upstairs and the 256 downstairs).

Still getting the "empty slot" condition.

I don't have Apple Care, I bought it second hand, this means I'm stuck with a powerbook with a half-useful logic board? sheesh...

Two questions:

1. Are there 2GB cards out there for this model of Powerbook

2. If I sell it, what would be the reasonable price to ask, taking in account this defect?

Thanks