Dragon Age Origins Error Message

Whenever I start Dragon Age Origins (through a shortcut, the original .exe file, or through Origin) an error saying, "Failed to detect a supported video card.", appears. I'm using a PC, and I just recently uninstalled Nvidia(software) from my computer. Years ago, on the same computer, I had a GeForce GPU (don't know what kind). Now, I have an AMD Radeon HD 6700 Series GPU. My computer let me keep the Nvidia driver files that I must have downloaded years ago when I had the GeForce GPU. Then I uninstalled Nvidia by deleting the driver files from my control panel. Now that Nvidia(software) is completely missing from my computer, Dragon Age Origins does not work. With Nvidia, the game worked fine, but without it, it doesn't won't work at all. The new GPU (AMD) is actually supposed to be better, as it improved my computers graphics.  Cannot install the nvidia software as it cannot detect their GPU.