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No...it's desktop RAM. And why would you want 2 x 256 MB chips anyway? You already have that in your machine.

Use the online wizards at OWC or DMS to find the right RAM for your machine.
 
Damn. Okay this seems better.

512MB Samsung Factory Original PC2700 DDR-SO 333MHz Cas 2.5 200 Pin Memory Module for all PowerBook G4 'Aluminum' 12, 15 & 17" Models, all iBook G4s, iMac G4 1.0GHz+. New, Lifetime Advance Replacement Warranty. Same module Apple factory installed! (OWC27SAMSO512) more info...
 
Yep...that'll work. The cheaper OWC-branded ones at $49 will also be fine. I purchased that RAM (the 1 GB stick for $122.99) for my PB that's the same generation as yours and it's been fine. (Of course when I purchased my stick a year and a half ago, it cost $239.99.)
 
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