hey, i'm upgrading my RAM for my very first time ever, and i'm contemplating whether i need a 1 gb stick or 2 gb. im currently working on the 1.9 ghz 17" 512 mb imac, and mostly use it for playing civ four, word, email, internet, small photo/video editing crap. obviously i know the more ram i get the faster it goes, but the problem is when i'm playin civ four i notice some seroius lag, and i was mostly just wonderin if getting the 1 gb stick would fix it; cause money don't grow on trees. any feedback is much appreaciated.