It's most likely that some of the solder spots connecting the RAM slot to the board are broken/damaged. If either you or someone you know is VERY proficient at electrical work/soldering, you may be able to repair it. Beyond that, you probably need a new logic board, unfortunately.

[quote|Ben Eisenman]It's most likely that some of the solder spots connecting the RAM slot to the board are broken/damaged. If either you or someone you know is VERY proficient at electrical work/soldering, you may be able to repair it. Beyond that, you probably need a new logic board, unfortunately.[/quote]

I just wanted to add a couple of tidbits to Ben's post...

Have you tried different RAM modules to make sure they weren't faulty? Also, did you make sure that the RAM modules you tried were the correct type? They should be PC2700 modules.

If you did attempt to install different modules and neither of them worked, then most likely you'll need a new logic board.

[quote|Miroslav Djuric]I just wanted to add a couple of tidbits to Ben's post... Have you tried different RAM modules to make sure they weren't faulty? Also, did you make sure that the RAM modules you tried were the correct type? They should be [link|/Apple-Parts/PC2700-1-GB-RAM-Chip/IF111-021PC-2700|PC2700 modules]. If you did attempt to install different modules and neither of them worked, then most likely you'll need a new logic board.[/quote]

Thank you for your replies. I did use a known good module from another 12" PowerBook (867mhz) but now that you mention it, I realize that they are PC2100. Will the PC2100 module not be recognized at all in system profiler?

Thanks again for your answers.

[quote|gwrivest]Thank you for your replies. I did use a known good module from another 12" PowerBook (867mhz) but now that you mention it, I realize that they are PC2100. Will the PC2100 module not be recognized at all in system profiler? Thanks again for your answers.[/quote]

Officially, Apple prescribes PC2700 RAM for the 1.5 12". Unofficially, the PC2100 may or may not work. I would definitely recommend tracking down some PC2700 RAM to test.

Shameless plug: we sell PC2700 RAM here.

[quote|Ben Eisenman]Officially, Apple prescribes PC2700 RAM for the 1.5 12". Unofficially, the PC2100 may or may not work. I would definitely recommend tracking down some PC2700 RAM to test. Shameless plug: we sell PC2700 RAM [http://www.ifixit.com/search?query=PC2700|here].[/quote]

Thank you. I will try to find a PC2700 module and try it out.

[quote|gwrivest]Thank you. I will try to find a PC2700 module and try it out.[/quote]

I found some PC2700 ram and it recognized it right away :-) I would just like to say a big Thank you to miro for your suggestion to make sure that I was using the right Ram type. I had just assumed that the 867mhz PowerBook used the same type of Ram as the 1.5ghz PowerBook. Thanks again.

[quote|gwrivest]I found some PC2700 ram and it recognized it right away :-) I would just like to say a big Thank you to miro for your suggestion to make sure that I was using the right Ram type. I had just assumed that the 867mhz PowerBook used the same type of Ram as the 1.5ghz PowerBook. Thanks again.[/quote]