“Do you need a different operating system to install the full 24 GB of RAM on this system? I was looking at a Dell XPS system that has an option to expand the RAM to 24 GB, but it can only be done if you have Windows 7 Ultimate installed first. It won't do it with the Premium OS. If I buy your HP Elite PC, will I need to upgrade to Windows 7 Ultimate before I can install the full 24 GB of RAM on it? Thanks.”