Hello Well in the end i finally ordered an i7 imac refurb, i wanted a mac pro but just could not afford it in the end and weighing things up it seems the right decision for me. I wanted to ask a question about upgrading the ram. Is it still best to install in pairs? I have the choice of putting 1 x 4gb stick in or 2 x 2gb sticks in to make it to 8gb ram. I'd rather buy the 4gb as it would save me money in the long run but remembered something about installing in pairs made the computer work better.