Well, I've experienced trouble in many cases with ATI cards - however, I'm not referring to difficulty with commercially available games (that hasn't happened for years), but rather with games in the course of development. When working on Dogfight 1942, each time we produced a build with any new graphical features, the programmers had to produce a special alternate executable and DLLs for me because of my ATI card. It goes without saying that the final release version was able to handle both NVidia and ATI, but in development, this wasn't a given. Most of the team used NVidia cards because that's what's most common. So every new feature was coded on an NVidia, and would either work or not work on ATI, we usually wouldn't know until somebody actually tried it. And of course, our graphics programmer was very experienced, and the moment a problem came up, he would usually figure out a solution very rapidly.