I've read a couple of threads posted recently on this topic already however I haven't come across a definite answer yet. My questions: 1) What is the difference between cl7 and cl9 ram? (from what I'm guessing it has something to do with timing and/or latency) 2) What does the iMac ship with? 3) Will the 2 x 4 gig cl9 OWC ram I have ordered (8 gig to go with the 4 already in there) have any issues if there are differences? Cheers.