converting from system 9 question

Welcome to the wonderful world of OS X. To answer your first question, no you can't. Why? Because you don't have to. You will never run into that problem on OS X because the OS knows how to handle memory well.

Also you can't upgrade the graphics card on a PowerBook, its an integrated component. In terms of upping performance, other than adding RAM it is possible to put in a bigger HD but considering how big the one that comes stock is you should be fine. Laptops just aren't designed for modifiability.

 

If you keep Mac OS X up to date you will certainly see a performance boast

For example the newer system 10.3 (Panther) i find is alot more responsive and quicker than the previous system, Jaguar. This is because Apple optimize the code with every new release so you can be sure that everything will go faster with the newest system

Apple also updates the Graphics drivers from time to time, these updates tend to add a few more frames per second onto your card