Pismo memory oddity?

[ktkm]

A couple of months ago, when OWC had a good deal on PC100 SO-DIMMs, I thought the time was due to upgrade one of my Pismos to 1 GB of RAM from 384 MB. But after installing two fresh DIMMs, the Pismo could only see socket J1—and with J2 gone, I thought a nice re-seating was in order. However, no luck. In order to rule out the possibility of faulty memory, I have swapped the DIMMs individually in socket J1, but with no result. I have even tried two other daughter boards (three in total) in two different Pismos, and in combination with 64, 128 and 256 MB sticks, and so far, the only combination that worked was with 64 MB—giving 576 MB in total. Is this a PC100 limitation? Do I need to use PC133? Any clue is appreciated.

 

[MacUp72]

Have you cleaned the RAM sockets? I bought the cheapest pc133 512MB so dimm I could find on eBay/amazon and my Pismo 400 and 500 ran well..maybe you could update your Pismo firmware? I have found this on my Pismo CD, when you dont have the right (FireWire G3 PB) model, it wont install.)

 

[Phipli]

Contact OWC.

They may have sold you incompatible RAM. Although it is hard to tell because your post says what you tried, but not the outcomes.

Previous potentially similar thread :

iBook Clamshell - Only Detecting 64MB of 512MB RAM Stick?

I just installed a 512MB RAM stick from OWC into my clamshell iBook. However, in Apple System Profiler, it's only showing the stick as 64MB (plus the 64MB built-in to the logic board, so 128MB total). I'm running Mac OS 9.2.2. Normally I'd assume that I got a mislabeled part, but since I assume...

68kmla.org

Note both my Pismos have 1GB RAM, it is possible.

 

[ktkm]

Have you cleaned the RAM sockets? I bought the cheapest pc133 512MB so dimm I could find on eBay/amazon and my Pismo 400 and 500 ran well..maybe you could update your Pismo firmware? I have found this on my Pismo CD, when you dont have the right (FireWire G3 PB) model, it wont install.)

Cleaning the RAM sockets didn’t do anything. I’ll check out the Firmware update. Thank you!

They may have sold you incompatible RAM. Although it is hard to tell because your post says what you tried, but not the outcomes.

When I did some more tests with only J1 occupied, one of the 512 MB OWC sticks acted up which resulted in a double beep at boot, so I guess something is wrong with at least one of the OWC memory sticks, and J2 doesn’t seem to be able to take memory of any kind anymore. Perhaps the OWC memory harmed the daughter card, or the MB is busted from all the swapping. Thanks for the thread!

 

[3lectr1cPPC]

Sounds like that one stick is bad but I doubt it killed J2. RAM slot failures (usually due to cracked solder joints) are not at all uncommon in laptops. Usually it's ones from a few years later that have this sort of failure (thanks to early lead-free solder being garbage), but it can happen in anything.