Share

Arnold GPU - Arnold User Guide

Supported Features

Arnold GPU supports a set number of Arnold features, including arbitrary shading networks, SSS, hair, atmospherics, instancing, and procedurals. See here for a detailed list of Arnold GPU features and known limitations.

System Requirements

Arnold GPU works on NVIDIA GPUs of the Ada, Ampere, Turing, Volta, Pascal, and Maxwell architectures. Multiple GPUs will improve performance, and NVLink can be used to connect multiple GPUs of the same architecture to share memory (On Windows, we recommend enabling SLI as well).

  • See the full list of supported GPUs.

  • See the Arnold system requirements for the recommended drivers.

Selecting a Render Device

You can easily switch between CPU and GPU with a single click. You'll find a new Render Device setting in the Render Settings > System section in the Arnold plugins.

You can use CUDA_VISIBLE_DEVICES (environment variable) to limit which GPUs Arnold (and any other Cuda-based application) can see.

Matching Noise on CPU and GPU

Matching noise can take a little experimentation because Arnold GPU uses Camera (AA) sampling only. We recommend you also use Adaptive sampling. Here are some guidelines:

  • Set the Max. Camera (AA) in the range of 30 to 50 (depending on the scene, you might go closer to 100). In general, the max samples should be a large value. A large max samples means that the quality is controlled by the noise falling under the threshold, instead of by clamping to the max AA.
  • Set the Adaptive Threshold to something like 0.015 or 0.02. For a noise-free render, lower the threshold value, maybe even as far as 0.010.
  • Set the Camera (AA) samples to around 3 or 4. One of the few reasons to go higher with AA is for motion blur. The higher the number of Camera (AA) samples, the less of a speedup you'll get from adaptive sampling.

Was this information helpful?