Maxing out your RAM can't be a bad thing. However, if you don't have any RAM intensive programs and you don't do video editing then you may personally not find much advantage to upgrading your machine. PC 2700 is cheap nowadays (I think that is what your powerbook takes) so upgrading should cost you less than a hundred bucks.
Open up "about this mac" from the apple menu on your menu bar. Click on more info and copy your serial number... go to this site LINK and paste in your serial number in the "Find by Serial Number" box and click the magnifying glass. This should take you to your machine's specs page and tell you what upgrades you can make.
cheers
grim
Would it be beneficial (vs cost) to upgrade from 1gb ram to 2gb? I am running 10.4.10 on a 1.67ghz powerbook G4. The machine is not used for any particularly intensive computing. Just wondering if there would improvement by upgrading. Thanks for any and all input.

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