I was thinking of adding a stick of 512 MB ram into my PB (G4, 1.5ghz, 128vram). But I was just thinking...Do I need another stick? (I know, more memory is ALWAYS good, but is it NECESSARY?) The apps that I usually use (or have open) are Msn Messenger, MS Word, Safari, Mail, iTunes, iCal. I already have 512 MB (2x256) in the PB already. So do I need more? Will it make it "faster"?