A:Answer Look up your serial number on the Apple support website. This will tell you the maximum amount of RAM your machine was tested with. However, it is fairly well known that larger sizes can work as RAM cards in these sizes may not have been available when your machine was manufactured. As for the speed, most of the time (most) you can easily use RAM that is rated at a higher speed than the original RAM for your machine (i.e., installing 1600 in 1333 slots), it will just slow down to what your machine uses. Make sure there is an option for returning if it doesn't work.
