Paul is vision impaired and has an eight year old iMac. How can he update it? Leo says that as long as he can update it to the latest OS, he'll be OK, and it sounds like Paul's is updated. But sooner or later, the machine will be left behind. Should he buy a new one? Leo says these days, computers aren't that much faster from one model to another. The improvement in speed really comes with a solid state hard drive and faster memory, though.