Steve has a 2009 iMac and he's been waiting to upgrade. Now he's ready to get a 27" model, but it says he can only upgrade RAM to 32GB with the midrange models. Steve has read that he can go up to 64GB and it will work. Jason says that the midrange can go up to 64GB, but the lower end is only up to 32GB from Apple. Third party RAMs chips are available, but Apple would rather he spend $200 more to get the next level iMac. He advises buying the iMac with the least amount of RAM available and then upgrade the RAM from a third party. OWC and Crucial are good places to get them.