How to Get Your Mac to Recognize Newly Installed RAM

by Ross McKillop on January 19, 2011

If you’ve recently upgraded the RAM on your Mac, and it still lists the old amount of RAM as being installed – this tutorial will help resolve the problem.

  1. To view the amount of RAM installed in your Mac, open the System Profiler by going to Applications -> Utilities -> System Profiler. In the Hardware Overview window, look for the Memory: section. As you can see, my MacBook Pro has 2GB of RAM installed.

  2. click to enlarge

  3. If after you upgrade (add) more RAM to your Mac, and it’s not listed as being installed – first check to make sure the ram is “seated” properly in the memory slots. If it appears to be installed properly, reboot your Mac while holding down the command + option + p + r keys.

    Wait until you hear the startup “chime” twice, and then let go of the command + option + p + r keys. This is known as “zapping the PRAM”. When your Mac starts up again, relaunch the System Profiler, and now your ‘proper’ amount of RAM should be displayed (in the example below, 4GB).


  4. click to enlarge

  5. That’s it!