FYI: The Intel Core i3 CPUs as used in the new iMacs are limited to 16 GB RAM as per the specifications on Intel's web site. That's 34 bits of physical addressing.
Sad to say, all of our modern computers would be far more powerful if only developers could get a grip on reducing software bloat. It was more than thirty years ago that I learned Unix on a Digital pdp-11/70 that had only 22 bits of addressing (4 MB core RAM). And there were always multiple users on the timeshared machine.