After making a dream mac pro configuration on the apple store (come on, everyone has done it at some point ) I wondered about the information that they gave to justify the frighteningly high prices for their own RAM. For those who haven't seen it, it goes like this: Please note: Apple created a more robust thermal specification for the Mac Pro FB-DIMM heat sinks that provide more efficient cooling than many other FB-DIMMs. These FB-DIMMs require less airflow to stay cool and allow the internal fans to spin at slower speeds, improving system acoustics. FB-DIMMs made by other manufacturers that do not include a sufficient heat sink may cause the fans to run faster (and louder) or the memory chips to run slower so as not to overheat. Is this statement really true, or at least true to a certain degree? If so would 3rd party RAM really make a noticeable difference to the Mac Pros performance? And one last question, would it be a big enough difference to justify buying apples 4x2gb for £940 vs crucials 4x2gb for £210? Just a thread made out of curiosity, as i know i won't have enough money for a mac pro for a long while just yet, but i'm sure there are some people who would like to know.