Yes I think you'd notice a pretty big difference, mostly at high resolutions/details and in newer, more intensive games of course, but all around it'd be a lot faster. Visual quality is subjective, and personally I went from a Voodoo Banshee to a Radeon 64 so it's not like I can compare Geforce vs. Radeon visual quality. However I often hear people say the Radeon has superior visual quality (not as much in 2d anymore since it's gotten better with GF3s) but that's just what I heard and I don't know if it's true or not.