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PowerBook G4 A1106 possibly bad RAM socket repair?

Baldung99

Baldung99

macrumors member
Original poster
Jul 8, 2019
75
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It's a 15" PowerBook5,4 (G4) A1106. I've been using this particular laptop for about a year with absolutely no issues until a week or two ago when I noticed it would only recognise 1GB instead of 2GB of RAM that are installed. The RAM sticks are fine, I checked that. So it only really leaves the slot as the culprit. How would I got about fixing it with only really basic tools? The only reason I'm hoping it's not that bad is that sometimes the RAM in that slot will indeed be recognised. Like now - I'm typing this post on said PowerBook with 1 GB of RAM installed in the lower slot.

Now granted, this laptop is mostly used for playing early 2000s games and it can do that with 1GB of RAM just fine. But it's really the second laptop that's "ready to go" and also has some modern features like WiFi and Bluetooth. So it's also serving as a backup in case my MacBook Pro decides to malfunction... but browsing the modern web with only 1GB of RAM is definitely not happening.

It hasn't had any other hardware problems - save for the original hard drive dying yesterday. Although I wonder... did I cause that? I've been tinkering with other laptops of that era and until recently, the only two 1GB sticks of DDR RAM I have had are those in the PowerBook. And since the RAM access area is cramped to say the least, oftentimes I would accidentally pull the DIMM in lower slot - the one causing me problems now - only partially out. I guess that could bend some pins, but then I haven't touched the RAM in months so I don't know.
 
Those things quite frequently suffered from RAM slot failures. Afaik there‘s little you can do apart from changing the logic board.
 
That’s right. There is no easy fix for a failed RAM slot. Some things that are worth trying first though;

1. Rotate and reseat the RAM modules.
2. Spray a little isopropyl alcohol on a cotton bud and wipe the slot and the gold connectors on the modules (in case of very light corrosion/oxidization).
3. Reseat and try again.

I have a few PowerBook G4 15-inchers with failed slots. It was a common fault of this model.
 
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AphoticD said:
1. Rotate and reseat the RAM modules.
2. Spray a little isopropyl alcohol on a cotton bud and wipe the slot and the gold connectors on the modules (in case of very light corrosion/oxidization).
3. Reseat and try again.
Click to expand...

It works but only for a limited amount of time. I ordered another logic board... I hope it arrives.
 
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If you can find a single 2 GB RAM stick for your PowerBook then you should be able to use 2 GB of RAM again even though one of the slots is defective. I can't tell from my own experience since mine does not have this defect but I've heard various times that it can utilize the maximum amount of memory even from one stick only.
 
netsrot39 said:
If you can find a single 2 GB RAM stick for your PowerBook then you should be able to use 2 GB of RAM again even though one of the slots is defective. I can't tell from my own experience since mine does not have this defect but I've heard various times that it can utilize the maximum amount of memory even from one stick only.
Click to expand...

Doesn't this only work with A1138/A1139s, i.e. DLSDs?
 
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Amethyst1 said:
Doesn't this only work with A1138/A1139s, i.e. DLSDs?
Click to expand...

Hmm, I thought I heard it in conjunction with the A1106 series but I could be wrong ...

forums.macrumors.com

Strange issue with PowerBook G4 and install media

This is good to know. Some time ago my early 2005 was randomly kernel panicking every hour or so and I suspected that the RAM itself or the slot is slowly dying. I stopped using the machine for 2 weeks because I couldn't really get stuff done due to the annoying kernel panics. I didn't ran ASD...
forums.macrumors.com forums.macrumors.com

Edit: Well, it looks like the single RAM stick 2 GB option is for the A1138/A1139 only but I don't know if anyone actually tried a 2 GB stick in an A1106 ...

This might be interesting to read:

forums.macrumors.com

PowerBook G4 15" Lower-Memory-Slot Failure

Got a 15" PB today. After the first great impression about the 'Book' the disappointment followed really fast : the lower memory slot doesn't work. Searching for that issue I've found endless complaints about that hardware-problem. So either live with 1GB RAM in the upper slot or get rid of...
forums.macrumors.com forums.macrumors.com
 
Bumping this thread, as I just received a pristine 1.67 15" Powerbook, unfortunately it has a dead lower slot. I found this post on the apple forums about using Open Firmware to re-map the memory and it actually worked. Posting here for everyone else:

"Subject: Powerbook G4 Disabled Lower Memory Slot Fix
Hi Guys, Here is my solution for the disabled lower memory slot that has plagued many Powerbook users. Unfortunately it is not currently a permanent fix, but I submit this to you in the hope someone will be able to come up with a proper solution. Little testing has been done on this fix, but I have trialed it on my Powerbook with 100% success.
Kind Regards, Jonathan T.
here is a solution to the problem, sort of.
i confirmed my lower slot is not fried by starting up with a single dimm in the lower slot. however it still will not recognize the lower dimm if there is memory in both the upper and lower. this may be different to what others are experiencing so your mileage may vary.
####NOTE THIS INVOLVES THE USAGE OF OPEN FIRMWARE, YOU COULD PERMANENTLY DAMAGE YOUR MACHINE FOLLOWING THIS PRODECURE SO PERFORM AT YOUR OWN RISK, I WILL NOT BE HELD LIABLE####
anyway as i said, my powerbook was physically detecting the ram in open firmware, simply not mapping it to any address space.
logic dictates that if the ram isn't properly mapped to an address, it will not be visible in mac os x. thus the ability to artifically reduce the size of your system ram in open firmware by changing these mappings.
1) first of all a note about module sizes. sizes appear to be in hex.
- 10000000 = 256mb
- 20000000 = 512mb
- 40000000 = 1gb
- and so forth...
you need to use the sizes above to map your ram to relavent address space.
2) next boot into open firmware. do this by holding cmd opt+of just after the boot chime of your macintosh.
3). this will bring you to the white open firmware prompt "0>". from here you need to navigate to the memory device tree by typing:

0> dev /memory

to display the details about the current memory mappings type:
0> .properties

this is an example of how i mapped my powerbooks memory modules to address space.
0> 0 encode-int 10000000 encode-int encode+
0> 10000000 encode-int 40000000 encode-int encode+
0> encode+
0> " reg" delete-property
0> " reg" property
0> mac-boot

the first line loads onto the OF stack the location of my first memory module. in this case it starts at address space 0 and is 10000000 (256mb) in size. 
the second loads my second memory module onto the stack starting at address 10000000 (directly after the first module) and is 40000000 (1gb) in size. the third line encodes the two lines above together on the stack. the fourth line deletes the current address space mappings (the contents of the " reg" property). the fifth pops my new memory mappings off the stack and onto the " reg" property. finally the last line starts the boot process for your mac. check system profiler and both dimms should be registering now.
6) There are two problems I can see with the use of this method. First of all it is not persistant, when you reboot your machine these mappings will be lost and you will be back to square one. Second, and this is the biggie, why is open firmware not doing its job and mapping both modules properly! is there a problem with it gauging the size of the memory in the lower slot when two modules are installed (i.e. faulty module)? or is this just a firmware bug?
Anybody have any answers? Anybody at all?
-Jonathan T."
 
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