Ok, with reference to your first post with screen shots, the second screen shot is only an information screen. There is nothing for you to manually change here.
When you install new RAM, assuming it's working ok, it will automatically be shown here. Memory updates rarely need any User intervention, apart from occasionally having to confirm the change on the first boot after upgrading. If you are having an issue with your new RAM, try moving the existing one to the second slot. If it will boot like this, the information screen should update to reflect the change. Then try your new memory stick on its own to see if it works.
What happens when you install the new memory and also what type and size is it?