Doom 3 Performance: Part 1
When first loading up Doom 3, the game automatically finds the best quality setting for your particular system and enables it. There are four different quality modes: Ultra, High, Medium, and Low. Ultra is the setting that will be most useful in ATI and NVIDIA’s next generation parts that will run on 512MB, High is the setting of choice for high end cards that have 256MB of ram, Medium is for mid-ranged cards running on 128MB, and Low quality is for the low-end cards running on 128MB of memory and below.
In the system menu you can also chose to go into the Advanced Options screen, which allows you to turn on Anti-Aliasing, VSYNC, and in-game special effects.