Medium Quality 1920x1200 Performance
As we commented earlier, ideally we like a minimum frame rate of 60fps as this ensures perfectly playable performance regardless of the action on screen. However, we have found that for the most part 40fps does provide acceptable performance. Based on those rules, the Radeon HD 4770 is the slowest graphics card we would recommend when playing BioShock 2 at 1920x1200 with the medium quality visual settings.
The Radeon HD 5750 was only a fraction faster than the Radeon HD 4770, while the Radeon HD 4830 was noticeably slower. Both the Radeon HD 4830 and GeForce 9800 GT hit a minimum frame rate of 33fps, while the old Radeon HD 3850 matched the new Radeon HD 5670 with a minimum of just 29fps.