Hi there. I have a 1.83 dual Core Duo Mac mini with 1 GB of existing Ram (purchased directly from Apple store about 1.5 years ago). Recently, I called a local Apple dealer about upgrading my mini from 1 GB to 2 GB RAM. They said I will need to have a new "pair" of 1 GB chips installed (2 new 1 GB chips that match eachother to total the 2 GB upgrade). Is that true, or can I just purchase one additional 1 GB chip to go along with the one I already have installed)???? I'd rather not have to spend the money if it won't make much of a performance difference. The guy I talked to said that I need to get two so they match exactly or the performance could suffer and the mini could run slower. If I do get just the one chip, how bad could the performance suffer??? Will it still be faster/smoother than the 1 GB I currently have??? Is it typical for people who upgrade the RAM to get the two chips at the time of the upgrade. I just feel like it is a waste of money and a chip that I already have. But I'll do it if the performance will be noticably better with the two new chips. Any feedback will be greatly appreciated. Thanks!