Nvidia tends to have better drivers but ATI usually has more power or depending on what you want they can also be a bit cheaper but it does need a bit of fiddling around. Also you should not be upgrading your graphics card every few months anyway that is really unnecessary I mean would you buy a new xbox or PS3 every year or every new model? Probably not. While graphics cards are a bit different at the least every year or 2 you can upgrade them to be honest you can get away with longer I know I have.