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• XPU currently requires a CUDA-compatible GPU to be installed, even if the intention is to run only in CPU mode.
• Behavior of XPU when it runs out of memory on your GPU:  XPU will crash if it runs out of memory on your GPU.  If you are running XPU inside of Maya, Houdini, or Blender, this will bring down your application as well.  Be sure to save often.  We are going to work to mitigate the two biggest causes of this condition.
• If you have more than one GPU, we allow you to specify which GPU to use with XPU, but do not yet support the ability to use more than one GPU at the same time.
• Releasing a license:  It is possible to get XPU into a situation where it doesn't release the license back to the RenderMan license server.  If this happens and you end up using all of your licenses, just restart your application (Maya, Houdini, Katana, or Blender) and you will be able to continue your work.

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