Hey guys, I've done a lot of research, and I've posted about this before.. but got no answers. I'm gonna keep it short and sweet this time and not go too into detail. I have an 27" iMac 10,1 (late 2009) model. It supports up to 16GB of DDR3 PC3-8500 1066MHz SO-DIMM memory. To ensure full compatibility, I am looking to purchase 16GBs of RAM and will be replacing the original factory installed RAM, as I understand different chips can cause problems. MY QUESTION: Must I buy 1 package with 4x4GB chips... or can I buy 2 packages with 2x4GB each? Will either of these options make a difference in compatibility?