Removing all traces of personal information from computer

I'm trying to remove all traces of personal information on my computer before returning it. The one thing I have not been able to do is get rid of my personal information that pops up in my Razer account. If I hit Start/Settings, the razer account stuff pops up. It has my name and email address, and I cannot see how to get this information off the computer without also deleting my razer account, which I don't want to do. I don't want someone else getting their hands on any personal information, but I have not yet been able to figure this one out. Also I need to remove my name from the login page. How do I do that?