In order to run Viewport 2.0, you must have the correct graphics configuration and graphics driver version. For information about Maya certified graphics cards and the most up-to-date driver versions, see Maya Certified Hardware on the Autodesk Knowledge Network.
See also http://www.autodesk.com/hardware.
For scenes with large amounts of textures, geometry, or cached animation, it is important to take note of the amount of available GPU RAM on your video card.
If your GPU RAM usage is very close to the GPU RAM limit of your video card, your textures may not load, and your scene appears in shaded mode. An error message appears indicating that the texture RAM limit has been exceeded, and suggesting that you reduce the Max Texture Resolution clamp. See Maximum Texture Resolution Clamping for more information.
To check the GPU memory usage of your card (in MB), use the command ogs -gpu.
To check the GPU RAM limit of your card, refer to the Output Window of Maya.
Viewport 2.0 manages the amount of GPU memory it uses. Working with complex scenes containing large numbers of objects or high resolution textures, you may need to reduce the amount of memory usage. Here are some guidelines:
Running multiple Maya sessions; or, running Maya simultaneously with another 3d program, requires extra GPU memory. If Maya is running alongside another 3d application, it does not automatically detect that it needs to share memory with that other application, and therefore may inadvertently exceed the GPU memory limit.
You can set the MAYA_OGS_GPU_MEMORY_LIMIT environment variable to override the memory detection in Viewport 2.0 and manually set a lower memory limit to reserve GPU memory for an alternate 3d application. Set MAYA_OGS_GPU_MEMORY_LIMIT to the memory limit in MB. For example, to limit Viewport 2.0 on a 2GB card to use only 1GB, set this environment variable to 1024. The output window confirms that the memory limit has been artificially set.
This may improve performance in the instances where you are running a 3d application simultaneously, but it decreases performance otherwise, and therefore should be used with caution.