You don't need more RAM in your system though, as with most things related to graphics, more graphics RAM on your graphics card is helpful. Unless you are working with video while working with audio, don't worry about it. I've been running dual monitors since the early 2000s and even with those graphics cards I never had trouble. I find it easier on the eyes to have two of the same displays though. Back in the day I had a 64MB ATI card and I ran dual 1280x1024 CRTs with no issues at all.
If your computer has two display ports hook it up and you'll never look back. Gaming on two screens at once will require a lot of horsepower on the graphics card but day to day use and anything in the studio won't be an issue at all.
Robert