Viewport 2.0 platform limitations:
Possible slowdown or instability due to memory management issues on Mac OS X
You may encounter either extreme slowdowns or instability due to memory management issues on Mac OS X.
To possibly alleviate this problem, set the texture size used for viewport display when loading in file textures for the renderer. Do as follows:
You can also set this environment variable: MAYA_OGS_CPU_MEMORY_LIMIT (to a value in MB) to the amount of memory you anticipate using for the renderer. The value should be smaller than the actual amount available on your machine.
Possible instabilities on Mac OS X for graphics cards with less memory
When working in Viewport 2.0 on Mac OS X (10.6.x), instabilities may occur when too much graphics memory is used. For graphics cards with less memory, this situation may occur more frequently, since the memory threshold is smaller. A graphics card with 1GB of VRAM or greater is recommended for the Mac OS X platform.
Note: On Apple computer systems shipping prior to 2009, you may see the option to enter Viewport 2.0. Be aware that these systems do not meet the minimum specification for Viewport 2.0 and may cause Maya to stop unexpectedly and you may lose your data.