So I bought a mini about a week ago and want to upgrade the ram. Initially I wanted to get a 512mb stick to add to the 512 it already has, but then I discover its (2) 256 sticks. I saw something on OWC that said "for best performance used equal amounts of ram in each slot." So is it not recommended to use a 1gb stick in 1 slot and nothing in the other? Should I just go with (2) 512 sticks, or could I get a 1gb stick and then use one of my 256mb sticks, so I'll have 1.25gb? Will it really affect the performance noticably if the slots aren't equal?