my gateway is getting old and tired, so im buying a new computer, and i think im going with the i-mac 20. i have a few questions about it though. i was told that i dont need to upgrade the memory from a 1gb to a 2gb because it doesnt require it as much as windows xp does..is this true?? and should upgrade the graphics card from a 128 to a 256?? will be playing alot of games on it..any other feedback would be great!! thanks in advance..