Hi everyone I just ordered DDR2 4GB PC5300 SO-D KIT SPEED 667MHz, (2X2GB)KIT from frys for $22.99 after rebate. However I just realised I have a mid 2007 macbook and it says it will only support upto 3gb. Is this going to be a problem or will it still accept 4gb? Also what are your opinions on the extra ram? Did it make a significant performance increase? I currently have a 2.16 1gb white macbook.