Full-Scene Antialiasing Performance Impact
Now let us take a look on how full-scene antialiasing impacts performance of the NVIDIA GeForce 6800 Ultra when enabled. It worth to say that we intentionally decided to use 1600x1200 resolution since in 1024x768 resolution there are absolutely no performance drops when FSAA is switched on.
Both OpenGL games we used in our analysis behaved identically with enabled FSAA. Basically speaking, 2x antialiasing does not impact performance even in 1600x1200 resolution – thanks to outstanding fillrate of the NV40, while 4x antialiasing reduces speed, but not that tangibly. While none of you are probably going to enable FSAA 8x in 1600x1200 resolution, we still checked it out only to find out that even the GeForce 6800 Ultra cannot handle this mode properly from speed standpoint.
Performance in Direct3D games with FSAA enabled is absolutely exceptional. Modes 2x and 4x do not impact performance at all in Unreal Tournament 2004, while in Max Payne 2 the GeForce 6800 Ultra delivers 140fps with FSAA 4x which is more than playable. FSAA 8x still puts even the world’s most powerful graphics card on its knees, though, we still see that even in this mode some games will perform quite fast even in the highest resolutions.
To put it short, the new full-scene antialiasing approaches NVIDIA implemented into its new NV40 graphics processors resulted in exceptional speed and image quality. Generally, MSAA is “free” on the GeForce 6800 Ultra for the majority of games in the majority of resolutions, except 1600x1200, when antialiasing affects speed, but very slightly. Perhaps, hybrid FSAA 8x looks pretty negatively, however, keeping in mind the astonishing power of the graphics processors, some games will run pretty well in that mode, especially in relatively low resolutions, and the highest-quality antialiasing of NVIDIA’s GPUs will be utilized by consumers.