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This means of the modules has been unseated or one of your slots has failed. Check if your computer is covered under the slot repair program and get in touch with apple accordingly but first make sure your ram is seated properly and test both slots.

Edit: Ignore what i said, this is odd. The RAM is recognised at some point not just properly. What i suggest you do is reset your PRAM/NVRAM/PMU. Try these and see if there are any changes. Also there is a possibility your RAM stick was mislabelled in which case call up the people who sold the RAM to you and ask for an exchange.
 
Thanks for the fast response, I think it is seated correctly, i Have 256mb internally its just the new 2700 reads 512 :confused:
 
mdt562 said:
Thanks for the fast response, I think it is seated correctly, i Have 256mb internally its just the new 2700 reads 512 :confused:
Try Fry's Outpost customer disservice to see how much you are beaten and what hoops they will make you jump through for a swap.
 
I resetted the pram, nothing works. I guess they labled it wrong, thanks for the help guys i guess i have to go through a week of hell trying to get my 1gig.
 
I have the same problem with my 1 GHz 12". I took it in for repair and it is indeed a defective slot and thus a defective logic board. :(
 
Hey Guys, I bought an other corsair 1gb stick. It also reads 512mb :mad: So im in the process of taking it too the apple store. I bought this powerbook on the night of the tiger release and didnt buy applecare. But i think its still under its 1 year warrenty ( correct me if im wrong please ) So what do i do at the apple store ( ive never done this before ) ? Please help me before i goto the store and just stand clueless. And before i go...do i need to bring any papers? Thanks for any replies.
 
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