The listed Apple tech spec for upgrading to OS X Mavericks is a minimum of 2GB of RAM. If you have 2007 or 2008 Mac and have never updated your memory before, you may only have 1GB of RAM in your machine. If you only have 1GB of RAM, you will have to upgrade to the minimum of 2GB before you can install Mavericks. To check how much RAM your Mac currently has, click on your Apple menu in the upper left-hand corner and click "About This Mac." The line that reads Memory will tell you if your Mac has the necessary 2GB of RAM or if you will need to upgrade before you can install Mavericks.
Although Apple's minimum requirement is 2GB, our experience has been that Mavericks is very memory intensive. For this reason, we believe users will see better performance with Mavericks if they upgrade to 4GB of memory at a minimum, with an even better performance with 6GB of memory in the machine. Find out if your machine has been tested by Ramjet Labs to go beyond the Apple specification of 4GB, something we call Ramjet+.
The MacBook Air and Retina Models of the MacBook Pro unfortunately come with memory soldered onto the board and cannot be user-upgraded after purchase, so what you currently have in these models is your maximum memory. However, it should be noted all Retina MacBook Pros come with either 8GB or 16GB of RAM, which should be more than enough to install Mavericks. Owners of these machines should have no concerns.
The very earliest MacBook Air models that can upgrade to Mavericks (2008 and 2009 models) did come with the minimum requirement of 2GB of memory, but based on our expectations, may perform less than optimized. If you have already upgraded to Mountain Lion on your 2008 or 2009 MacBook Air, you should have a good idea of how your machine will run should you decide to upgrade to Mavericks.
Read on to find out about Mavericks compressed memory function and what it might mean for your Mac.
