I'm looking at buying a 20" iMac real soon and will want to get it to 2gb. However, I was planning on buying it from Apple with 1gb and then dropping in a stick of Crucial 1gb. Would this then not run in dual channel as they are not identical dimms or does it not matter what make they are, as long as they are both 1gb modules? Only reason I'm doing it this way as its cheaper than getting the full 2gb to start with. Chanks!