10.4.2 not recognizing extra memory module

Hi,
The same thing happened to me
But I was out of warranty. I bought my PB in 11/03.

So what what can I do?

I put 1GB stick to replace the 256MB in upper as the lower slot is not functioning and not recognized like everyone else. It works fine with the new 1GB in the upper slot while it is bothersome to know that the lower slot is not working, logic board that's connected is probably broken, and there is no chime at start-up, a typical synptom I heard. Hopefully, Apple will acknowledge this defect, and offer free repair. Until then, many of us with no warranty or apple care will have to get it repaired on our own or survive like I am doing with just the upper slot.

I've experienced similar to what's been reported here. Laptop slowed & crashed after installing 10.3.1 & upgrading RAM. Still under AC, Apple replaced Motherboard. Two months later, upgraded RAM again and again, bottom slot failed to recognize chip. Apple fixed MotherBoard again.

I am now running 10.4.3 w/ 1 GM in bottom & 256 on top. Every thing seems fine.

Funny thing is when I diagnosed the problem w/ the bottom slot (& I am far from a techie) after the 2nd incident and AFTER several other 1 GB chips did not seem to be recognized, Apple refused to accept my opinion. Nevertheless, they fixed it, but I lost some work.

This also happens on a 12" 867 MHz PowerBook G4 after upgrading to 10.3.9 and one of the software updates after it. Intermittent problem and a reboot usual recovers the memory.

Why would you put with this method of using your Mac. Send it in and get it fixed. I did and it works great. I sent it in with Patriot Memory and they did not pull the DIMM. They replaced the Logic Board.

William

I absolutely cannot believe what I've read here today. Count one more G4 memory slot victim with an 18 month old, out of warranty Powerbook. I kept muttering to myself "WHY didn't I notice sooner that my memory slot had failed?!" "WHY didn't I get the AppleCare plan?!" Now I'm just plain livid that this seems to be such a widespread problem - and that Apple's "extended repair" program for G4's with this issue only covers very recent Powerbooks. I've signed the petition and written to http://www.apple.com/feedback/, but not sure where to go next. I feel very let down by a company that I've bragged about for years.

Since Tiger, my instinct told me there was something not right with the frequency of kernal panics I was having, I turned a blind eye to the diminished ram profile, atributing this to an intermittent software glitch. I noticed some frizzling when installing 10.4.5 update, and the system profile now reports a failure of the lower chip. I can at least take confirmation from the above reports. I have registered my observations with apple, and signed petition;

http://lowermemoryslot.editkid.com/

Installed new 1GB Ram chip today, totalling 1.5GB. Feeling better now, must have had faulty ram from supplier. Fingers crossed!