I have a problem with my Window 7 Ultimate video card (WDDM). It said that it needs an upgrade for aero to....?

Work and I all ready tried the troubleshoot millions of times and it still said's not fixed. So, can somebody please help me upgrade my video card. Like a free legit software that's works and doesn't cost me money or, can I go windows update to get it or, do I need to update my direct X to get it or is there something else to do to Upgrade the video card (WDDM) that doesn't cost me money either.|||"Upgrade" means that you have to buy a better video card.